I work with an Badger 150, perhaps not one of the cheapest I admit. But, it has good qualities, you can change needles and heads from big, medium or fine and Badger is a brand that always can provide spare parts. I have mine for 20 years now, I've done lots of stuff with it and it still works as the day I bought it. Of course maintenance is everything, always clean it thoroughly after each session.
If you're looking to buy one always ask yourself what you want to do with it, If you're a beginner a single action airbrush something like this will be fine:
It's not thrown away money sometimes, for certain jobs, this model is more preferred than a sophisticated model. They can be used alongside.
Always make sure that you can spray solvents, like thinner or white spirit, with it, even if you are planning to work with acrylics. There are airbrushes with rubber fittings in them, that you can trough away when used with solvents, and they are not always the cheap ones.
If you buy a compressor, buy one that has a current airflow an air regulation unit, best is one with a small air tank attached. There are compressors when they compress air, they give little air-shocks, this is not a good one, so avoid buying one of these.
I hope this has made you a little wiser.