You will need a compressor that will supply the requied SCFM for HVLP paint guns. This is usually on the order of a 10hp motor compressor with at least 16SCFM, 100 plus gallon tank and 3 phase motor. You will need a decent dryer for the air supply.
DeVilbliss, SATA, and others make paint guns that are good quality. Be ready to spend at least $300 or more for a quality finish paint gun. You will need a primer gun too.
Also, to shoot the new paints, you will need a breathing system.
I would ask this question at one of these forums...
http://www.autorestorer.com/q_boards/body/index.cgi
http://www.autobodypro.com/wwwboard/wwwboard.shtml
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