Are negative pullups the best place to start?

Takes time to develop the strength to lift your full body weight doing pull ups or chin ups. Chin ups are easier because they activate your biceps. So, you might try to achieve chin ups 1st.

I don't think negatives alone will ever build up the strength necessary to do a chin or pullup because it's much easier to just let your weight drop than it is to lift it up.

The assistance exercises that should help are those that work your arms, shoulder girdle, pecs and lats, which would include (but are not limited to, in no particular order) : lat pulldowns, bent over rows, pushups, dips, bench presses and the overhead press. Throw in curls if you are going for chin ups 1st.

Difficult for men to do them and even more difficult for women because the upper body is one of the weakest parts of a woman's body. It's achievable for everyone regardless of gender but it does takes time, diligence and consistently increasing effort to acquire the necessary strength.

Good luck!

Yes! Negatives were what got me to my first pullup much more so than rows or assisted pullups. Frequency seemed to help a lot too. When I was dead set on doing the first pull up of my life, I was doing 5 sets every other day. Prior to that, I'd been doing around ~3 sets twice a week and progress was slow.

Negatives are one thing you can do to help build strength. Most of the time, unless you are really holding tension through the whole negative, negatives focus most on the top of the range of motion. Since you will have a spotter, try some spotter assisted pull ups. Bend your knees and have the spotter hold your feet.

Negatives are good but also try lowering a bar on a Smith Machine or something. Lay on your back, then pull yourself up.
Pull Ups are a staple of mine, and I can deadhang between 17 and 25 on any given day.
I started out not being able to do any just like you, so I know you can get up to at least 10 which is great for a lady.
Heck, there are females in our gym who smoke me on that pull-up bar, so who knows?
Good Luck...
PS:
Here is a video I made 2 years ago completing the 20 Pull Up Challenge...

I've had a decent amount of success with my clients by incorporating eccentrics at high frequency (for some people I'll have them do these every training day) and we build volume so that over weeks they are doing more and more total eccentrics.

We combine this with a variety of pulling accessories and it tends to do the trick.

Seems that right around the time people get mad at me for programming so many damn eccentrics, they get to the point of being able to do full chin ups. So I'm possibly annoying them into it

It's good to try a couple of pullup setups and figure out what fits you at your current weight/fitness level. Here's some options: 1) Negatives /w no assist, 2) negatives with band assist, 3) Pullups in different grips (palms in, palms out, wide grip, 4) pullups with weight hanging from waist, and my least favorite: 5) Pullup assist machine.

Negatives help you focus on improving your time under tension. For example, I'm happy if I can make my negatives slow enough that I do two in a 1 minute interval during circuit training.

I like bands for a lot of strength training stuff such as deadlifts, bench, squats, so I already have a variety of them sitting in my gym bag.

Re: SideSteel's post above: You are lowering the weigh during the 'eccentric' phase of the lift whereas you are raising the weight during the 'concentric' phase of the lift.