RE: Airbrush
I agree with 2fast any compressor will do. Check your local paper or even a local pawn shop. As far as an air brush goes i've found that a good quality airbrush is unbeatable. I prefer a dual action but they offer more flexibility in shading and things like that. If you simply want to mask off a section of the body and piant it then remove the mask and apply another color without any type of shading then a rattle can will work fine. I've even done a fading scheme with a rattle can. I painted the front of the truck black then dark blue then light blue then silver then to purple. My friends couldn't believe i did it with spray cans. Its up to you and your abilities.
Good Luck!
Rich