I've used Citadel Paints on Joes, although it will wear/flake around the figures' joints (I've yet to find a paint that won't!)
There's a Games Workshop store in Manhattan -- I'm 90% sure it's on W8th (was living in NYC for a year). They'll have paints, brushes and other supplies.
*I didn't do anything to this post. I accidentally hit EDIT instead of QUOTE cuz I was replying to this, uh post. Sorry.*
