Don't know how helpful this will be, I'm a little odd, but I'll answer anyway! ;-)

(1) What are the best socks for long distance running?

I'm a huge fan of Balega, but a pair i had for about 3 months has a hole! At $11 a pair, that hole makes me mad. Also, it's not unbearable, but i find them a bit warm for summer. I recently got a pair of fitsoks, they are light weight and i think I'm going to buy more. I quite like them.

(2) How useful is a GPS/heart rate monitor watch? What are the better brands/models?
I've got my garmin fr 220, I could live without it. I stopped using the hr strap because i just didn't like it. I'm not the right person to answer this one!

(3) Do you fuel before or during a long run? What and how often do you eat (and where do you carry it ?
I fuel before. I ran 14 today on two breakfasts with swimming lessons in between breakfasts. If it wasn't for the swimming lessons 1 breakfast would have been sufficient. So i carry a snack in my camelback or fuel belt, but because I eat before i generally don't need it. I carry baby food pouches, honey stinger waffles and jelly beans. I eat if I'm hungry, but that's rare. I may need to start using my snacks as my runs climb from 2.5 hours to 3. But maybe not. I do drink water on my runs though, helps keep the sinuses clear.

(4) Do you wear sunscreen and if so, what kind?
i wear cvs brand 50 spf for kids spray and the stick of California Baby for my face.. The spray is sticky but i forget about it quickly. I wasn't wearing it until i noticed how dark my tan was getting and i got freaked out.

(1) What are the best socks for long distance running?
This TOTALLY depends on you. My dad loves Wigwam Ironman Flash Pro socks. I love Under Armour Grippy socks. It depends on your foot shape, how hot/swollen your feet get over long distances, etc. I love socks that are thin, wicking, but don't have tight arch compression bands because my feet swell so much when I run that the bands make my feet ache. You'll have to find a pair you like and NEVER LET THEM GO EVER

(2) How useful is a GPS/heart rate monitor watch? What are the better brands/models?
GPS watch is AMAZING for long distance training. Takes the guess work out of pacing and distance. I can't imagine training for half or full marathons without one. A HRM though, I don't use one and have no desire to have one. I never push myself hard enough that I'd need a HRM, so I'm fine saving the money.

(3) Do you fuel before or during a long run? What and how often do you eat (and where do you carry it)?
I do both. There are a lot of varied opinions about this on the Long Distance board. But I like to get up about an hour before I want to head out the door to drink water and eat some granola. Then I take caffeinated Honey Stinger chews and eat a couple of those every 3-5 miles. I have a water bottle with a hand strap and a zippered pouch, so I keep an ID and my chews in there. The bottle gets heavy after a while, but I think it's better than a hydration belt; when I wear my Spibelt to carry my phone, my back is sore when I get done running

(4) Do you wear sunscreen and if so, what kind?
Yes! I wear a generic SPF 30 spray-on sunscreen on my legs/arms/chest/back, and I use Neutrogena SPF 70 lotion on my face. I like to use the Neutrogena on my face because it rubs in and never runs, so no matter how sweaty I get, I'm not tasting sunscreen.

As a distance runner who has also dealt with very early stages of skin cancer, I always tell any runner I know who asks...wear sun screen!!!!!! I use spf 50 sport and sometimes I reapply by running by my house. Do not forget your ears, especially the helix . that is where my issue was, I would do my ears but never really took careful time to get the helix and I paid the price. You don't realize how that part of your ear is just constantly exposed, and my doctor told me it is one of the most common areas for a runner to develop atypical moles and worse.

I'm not really seasoned, but these are my experiences so far (with my longest distance currently the HM and my longest training currently at 12 miles):

(1) I wear Feetures. I like them because they're not too pricey, and they're comfortable. The more expensive style (elites?) is pretty thin with a good amount of tightness for support.

(2) I love my Garmin 210 and wear it all the time, though I don't wear the HRM as often as I would like.

(3) I fuel before and during, though I've heard a lot of experienced people say they usually don't, and I'm working toward that. I like a bagel with peanut butter a couple hours before a long run or race. I'm still experimenting with what to eat during.

(4) I just got some CeraVe sunscreen and LOVE it. It's a physical sunscreen (mainly zinc oxide) as opposed to cheaper sunscreens that use chemical blockers. I don't really need much though, so the bottle is lasting a lot longer than I expected it would. It leaves a little bit of a white sheen, and I try to let it dry a bit before I put on my clothes. Even with liberal application of chemical sunscreens, I would still develop tan lines, which tells me they weren't super effective. I don't get any tan lines with the CeraVe. Did I mention I LOVE it? If you do get a chemical sunscreen, at least make sure the bottle says it's broad-spectrum (blocks both UVA and UVB rays).

Let's see...

Socks: i am a huge Belaga fan. They make sock in difference "weights" or thicknesses. I wear a very thin/light weight sock. Being in Mississippi, my feet melt! I also put deodorant/antiperspirant on my feet before my socks. That helps, too.

I do not wear sunscreen even though I know I should. It gets in my eyes and attracts bugs. Ick.

I carry a Nathan 22 oz water bottle with me from Feb/March through Oct. It stays warm enough here to need it. Most every run I do is at least 1.5 hrs or more, so I need to rehydrate. No belts or back packs. Chafing
issues.

As far as breakfast, grits and coffee before the run. I do not refuel during my runs anymore. I used to be a GU girl but have gotten away from that. I just live off the "fat of the land" and believe you me, there is plenty of that! HA!

I love my Garmin but no longer wear the HRM. It chafes me. Ouch!

I think that is everything. If I forgot something, I'm sorry. Good luck!!!

(1) What are the best socks for long distance running?
I like Balega the best. Hidden Comfort for long slower runs. Hidden Contour if I'm moving a little faster. I also like Wright and Thorlo Experia.

(2) How useful is a GPS/heart rate monitor watch? What are the better brands/models?
I have a Garmin 310XT and I love it. I use it to keep track of how far I've gone, how fast I'm going, and I use the HRM to manage my effort.

(3) Do you fuel before or during a long run? What and how often do you eat (and where do you carry it ?
I do not fuel before any runs (except half marathon races). I drink a cup of coffee and some water about an hour or so before I go and don't eat until I get home. My longest run has been 16 miles and I've been fine up to that distance. There are a couple of water fountains accessible where I run but I don't use them unless I'm out more than 90 minutes or so.

(4) Do you wear sunscreen and if so, what kind?
I usually run early in the morning, in which case I don't use sunscreen. On the rare occassions that I run in the afternoon I use whatever sunscreen is around (usually some kid specific something) and wear a hat.

(1) What are the best socks for long distance running?
Well during winter I love my smart wool and actually have some lightweight summer ones. I also have four pairs of Drymax from Road Runner Sports that I love. And a few pairs of Asics. Anything that helps you avoid blisters

(2) How useful is a GPS/heart rate monitor watch? What are the better brands/models?

I love my Garmin. It allows me to go run trails without mile markers. Is it necessary? No. But I do love it. I have the lowbrow model, the Forerunner 10. I am not really techy-I just want to know how far and how fast. My husband being a sweetie bought me the fancy 620 but I returned it. That thing was too fancy for me I don't have one w the hrm. I hate wearing the band.

(3) Do you fuel before or during a long run? What and how often do you eat (and where do you carry it ?

Well back in the day when I ran farther I carried water. But I live in hell, aka the South, so the temp and humidity kill you. Nowadays I am fine without it and when I was training for my half I didn't carry fuel. I probably will when my long runs go above that 13. I have used gels in the past. So gross. I like the clif blocks or the little gummy things.

I have a camelpak with a pocket. I run a lot of trails so water sources are either nonexistent or only suitable for my dog, who licks her own butt so isn't really a connoisseur.

(4) Do you wear sunscreen and if so, what kind?

My moisturizer has it in it. I probably should have extra. But I don't.

(1) What are the best socks for long distance running? There are lots of different kinds, and this is one of those things that you will have to figure out what works best for you via trial and error (kind of like shoes... the best shoes for me are not universally the best shoes for everyone)

(2) How useful is a GPS/heart rate monitor watch? What are the better brands/models? I have found it very useful in that I can keep an eye on my pace for longer runs, when it becomes more important to make sure you're hitting a certain goal (if you're practicing a certain speed to see if you can sustain it for the race), or making sure you're not going TOO FAST right in the beginning and then not lasting for the long haul. Garmin makes some "basic" models that are affordable, in the $130 range, which works for everything I need it to.

(3) Do you fuel before or during a long run? What and how often do you eat (and where do you carry it ? Before a long run, I eat very lightly, like I would before a race (bread with peanut butter, coffee, some water). I bring one water bottle during the run, and sometimes some fruit snacks or sports jelly beans (though I don't eat the whole thing). I carry the water bottle in my hand, and any snack I bring just gets shoved into my bra LOL! I'm flat chested, and I could easily run without a bra, and I joke that my bra is just a convenient snack pouch. Carrying a water bottle is annoying, especially because mine isn't even one meant for running (it's just a basic bottle, but I'm broke right now). I do an out-and-back trail run, so I'll leave the water bottle at the mile 4 trail marker, then pick it up on my way back out, so I'm not carrying it the whole time, but still have the option to drink water . I generally try to keep my fueling to a minimum on my runs, because there are ZERO places for me to use the bathroom out on that trail, and it's always populated enough where I can't really hide and find a spot even if it's an emergency!

(4) Do you wear sunscreen and if so, what kind? I wear sunscreen. I buy the kind that comes in a tube (kind of like an oversized chapstick), because it's the only kind that doesn't start dripping into my eyes if I sweat. That stuff is thick and feels like I rubbed vaseline all over my face, but it stays put and does its job! I also use a Halo headband that has a plastic band that redirects the sweat to run down the side of my face, which also helps prevent that whole sweat-in-my-problem I used to have.

Could some of you seasoned runners offer guidance on the following questions. My weekend runs are starting to get up into the double-digit mileage, so the things I put on and in my body are starting to matter more. Thanks!

*****

(1) What are the best socks for long distance running?

(2) How useful is a GPS/heart rate monitor watch? What are the better brands/models?

(3) Do you fuel before or during a long run? What and how often do you eat (and where do you carry it ?

(4) Do you wear sunscreen and if so, what kind?

Drymax 3/4 lite trail socks for everything.
Garmin time, pace, distance is all I need. You get what you pay for.
Eat normal before and after. Eat gu once and hour or so in training with water and each 45 minutes in a race of a marathon distance or farther. Ultras require for food than that.
Almost never wear sunscreen though some think I should. I've had melanoma skin cancer and my brother died from melanoma. I tend to cover up with a hat and long sleeves if possible.

I also hate wearing but spray no matter how bad the bugs are.