Badger makes one of the better Air Brushes...You can run it off of a small 2.5gal oiless compressor by turning the air pressure down, or buying a specific compressor made for them..
You can use regular paint, but it needs to be really thinned down with thinner and it takes a little longer to dry...
There are books (just like reloading manuals) on air brushing that will give you a basic understanding and some practice drills that will let you build some skills to do some really fine work, but it takes a good deal of muscle control and an artistic eye...
By the time you read the book, you will know the difference between the types of air brushes as well as how to get the best results from them...It's a whole 'nother educational program...
I did my first Air Brush project using DuraCoat paints with a hobby kit that I bought at WalMart that had compressed air for a propellant and a 'hobby' type brush...It was fine for painting a rifle, but pretty course for any fine detail work....