I also play warhammer, and 40k, amd warmachine (yeah, I'm a junkie!) I have a single action badger 200nh I use for base coating. You can hold enough paint in the jar to go through quite a few minis, at least 2-3 ten man squads without a refil. You can get this with 1 small and 1 lg bottle, plus the hose for $76.00
http://www.chicagoairbrushsupply.com/badeceset.html
A compressor will cost you a bit more, but not too much! $89.00 at Wallyworld gets you this. I used one of these for about 3 years before getting a bigger compressor that will do more than just airbrush.
http://www.walmart.com/ip/Campbell-Hausfeld-Electric-Oil-Free-Tank-Mounted-2-Gallon-Air-Compressor/11377676
So long answer, you can spend about $200.00 and get a very nice, versatile setup that will last a long time. Now start asking questions about paint!
Chris
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