It's a way painting, sort of, it's more durable than just spraying paint onto something. Most wheels are powdercoated, almost all engine parts that look painted, like intake manifolds, are powdercoated. There is a powder, of the color you want blown onto the piece, then it's baked on to form a paint-like finish. Pretty sure that's not exact, but gives a rough idea.
Edit: Here ya go...
Edit: Here ya go...