I am in the model railroad custom painting business. The airbrush I use and higly reccomend is a Badger Model 200C with a fine tip. It is a single action airbrsh with sever double action features that allows for fine control of paint and spray pattern. It may be a little intimidating durng clean up but if you follow the insturctions you will will be able to strip it down, clean it, and reasseble it practiacly blind folded after you use it about 10 times. I also reccomend getting an Air Compressor capable of about 50psi if you use acrylic paints or 35psi for solvent based paints and a Resavior tank. This is much cheaper in the long run than using those propellent cans and produces better results because you dont have to worry about running out of propellent. Several people also reccomend a regulator so that you can maintain constatn air pressure in the air hose but in my 10 years of air brushing I have never used one. What you do need however is a moistior trap. This keeps water out of the air hose to the air brush and keeps from contaminating paint.

I hope this helps.