www.epicpowdercoaters.com "You can get your rims done elsewhere but THEY WONT' BE EPIC!" <<-- I would bet $50 this company is not even 5 years old by the popular internet meme name.
I'm not sure I'd recommend doing it yourself unless you have a few practice items; sounds like a good way to end up with something you don't like. Ask a hot-rod shop or exhaust shop in your area, they'll probably have some experience in who to use.