I use one of the POS Testors cheap-o airbrushes that come bundled with a can of propellant. So far, it has been no trouble and has suited me well.
I might not trust it to do and complicated fades or camo detailing, though.
You can pretty much put any kind of paint you want through an airbrush, but make sure you have plenty of whatever you need to clean it well. I use acrylics, so I can clean up with water and a 50¢ toothbrush.
If you use enamel, but a jug of enamel thinner, or something just as effective. Just be careful, because the quickest way to ruin an airbrush is not clean it well enough.