easy way to start is to remove everything except for the a/c systems except the compressor, belt, and a/c switch on the dash. Then use a rubber hose with a small air filter an a tool oiler on it and plug that into the intake. Good compressed air will come out the other side of the compressor when you turn the a/c on and you can do what you want with it from there, some people put a quick connect end on it and have a hose they use for airing up the tires or for air tools, some people run it into a reserve tank for the same or if you ever get air lockers you can hook it up to those as well.
http://www.onboardair.com is a good place to start for more info, they have a links section where people have some examples of setups.[addsig]
