OK you want information, you got it...
Eastwood is a good place to start, but they are $$$$
Try
http://www.caswellplating.com/powder/index.html. They also have fourms here
http://forum.caswellplating.com/powder-coating-questions/Other places for products are:
http://www.powderbuythepound.com/catalog/index.phphttp://store.columbiacoatings.com/And don't forget to check ebay. Also while I applaud the ingenuity of making your own, Harbor Freight and ebay have complete guns\power supplys for $50. Just hook up to your air compressor.
It's pretty simple to get started, cheap also if you already have an air compressor. Buy the Powder coater and powder. Build a booth (I use an old metal clothes closet that I got free from craigslist), and get an old electric oven (also free from criagslist!). That's the basics. It's the other stuff that starts eating at your wallet. Things like a blasting cabinet to clean the parts, plugs, caps, masking tape, extra powder cups for quick color changes. And oh yeah don't forget the stripper, degreaser, metal prep, acetone, respirator, fan, filters, 20 amp breaker and 4 wire wire for the electric oven, etc. But the results are awesome.
I've attached before and after photos of a buddy's 79 mazda battery tray. Actually, the before picture is after blasting. It was originally a greasy, rusty mess. I blasted it and it sat for a few days, devoloping the flash rust you see in the before picture. I gave it a quick reblast, prepped it and shot it with flat black. The imperfections in the final product are in the metal itself. Rust ate away at some of the metal. Since most of the tray is hidden we elected not to sand the metal smooth. Still think it looks pretty good.