Classes for custom car painters?

I see all these professional painters doing custom paint jobs on cars and motorcycles and I'm really interested in learning how to get started on the basics. I've always been a very creative person and in highschool I kind of taught myself different styles of graffiti. I would assume that I need to take art lessons for basic shading, color schemes, etc, and after that I should probably go out and "apprentice" with some patient painter who is already established and willing to pass on what he/she knows. I was wondering if there are any trade schools focusing on car and motorcycle customization ONLY? Any info would be much appreciated.