Lifting heavy (at risk of sounding like a dimwit!!)

Heavy is relative to the individual

From the thread I answered this in a few hours ago

From a weight perspective it would be 85%+ of your one rep max for whatever exercise. In general though when people say it they are also referring to doing a routine focused on compound barbell exercises like deadlifts, squats, bench press, overhead press, barbell rows, pullups\chinups.

I'm 100lbs so What is heavy for me will probably be baby play for my 200lb body builder friends, so basically it is different for everyone, depending on your strength levels and such.

You might do well to read something like the New Rules of Lifting for Women, (I found it a little patronizing) but it should help you build a good routine, and how many sets and reps you should be doing in each exercise.

I work out from home, but I know I will need a gym at some point if I want to progress, I'm using all my husbands weights and bars, dumbbells etc...maybe you can afford a good dumbbell set with several weights so you have a range, you will generally need some heavier weighs when doing legs and bigger moves, and something a little lighter for arms and such, also you want to be able to make it heavier as you progress so loose weights are good, and you can usually find them second hand too...and don't discount body weight exercises too.

how long is a piece of string ?

seriously though, usually when people talking about lifting heavy, it's a weight that's 75%-99% of their 1 rep max for a given exercise. it doesn't have to be based on your weight at all, as there are women half my size who can snatch twice as much as me or more.

also if you're interested in getting stronger biceps, i'd suggests pullups and bb rows instead . if you're more interested in hypertrophy then stick with the isolation type stuff as opposed to compound lifts

Technique. Thats what you need to get down first, otherwise youll injure yourself. More muscle tone, means your metabolism burns a lot more. Muscle burns far more than fat.

There are a LOT of links and info if you search the forum as this has been asked many times.
A great source for form/technique videos is youtube - Mark Rippetoe. Also, get his book Starting Strength: Basic Barbell Training - it's an intense look at the main compound lifts (using a barbell) and a fantastic resource for the beginner lifter. I consult it all the time to tweak my form.

Usually lifting heavy, for most that is, means you are working out doing around 3 sets of 6-8 reps usually failing in between the 6-8. Its different for everyone so each person has to find there "max" and work from there

I've been lifting on and off for years and just got back at it at the beginning of August and the change I see so far is so motivating. Here are a few recommendations: "Fit For Life" by Bill Phillips (a friend of mine just got this book for 3 cents on Amazon used, of course, but he has a great program that I follow to this day). Also, go check out muscleanstrength.com. They have this awesome exercise video library that you can check out to learn dumbbell, barbell, machine exercises and what muscles they target. You really need to get a routine down (which is where Bill Phillips helped me). I lift as heavy as I can for 12/10/8/6/12 reps and increase the weight with every set. For my upper body alone I do a combination of 10 different exercises that take about 40 minutes to complete. An example of one of those sets is, I will do incline dumbbell curls and start @ 12 lbs. for 12 reps, then increase to 15 lbs. for 10 reps, then increase to 20 lbs. for 8 reps, 25 lbs. for 6 reps., then finally down to 20 lbs. for 12 reps. to finish off the set. The 25 lbs. is really hard as is the last rep set, but it is supposed to be. When this starts to get easier, I will increase the weight to 15lbs./20lbs./25lbs./30lbs./25lbs. for the aforementioned reps. Muscleandstrength.com also has some great calculators on their site.

I have all free weights and a nice weight bench at home in my basement, if you're interested in increasing your free weights at home or looking for a decent bench, people are always selling used weight lifting equipment for real cheap. Good luck!