Well I would like to get better at pinch harmonics. I can produce them at an audible level, but I`d like to get better. So what exercises are good?
Breakin` the Law!
Yeah that's pretty much your only bet. You could also try playing every note in a scale as a pinch harmonic. Play a two-octave scale so you can practice on all 6 strings.
Cemetary Gates - Pantera, Without Judgement - Death (High strings), Psychosocial - Slipknot (Low strings) . Just try adding them in songs that don't have very many, in spots that make it sound better. Thats what I did.
Well, I actually got a lot better after watching THIS. If you skip to scene 5, he'll do this thing about Pinches, and it actually helped me a lot, got me way better at doing it, I found it to be quite a good technique.
ESP Horizon II
LTD EC-1000
Ibanez MDB1

Morgan BC40
Koch Twintone II

Quote by -xCaMRocKx-

YouTube: more morons than Yahoo Answers and more hate than 4chan. It's the Internet's premier breeding ground of complete idiocy.
Killswitch Engage uses a shit ton of them live. Watch some of their live videos, and then trying playing with the real songs (adding the live pinch harmonics onto the real song). A lot of the ones they use live aren't actually in the real song.

Here's a little something to get started with that style of pinch harmonic.