I've gotten all of my keg conversion parts from bargainfittings.com. Their prices are awesome and the guy gets the products out the door amazingly fast. I think I'll be ordering up the camlock quick disconnects and silicon tubing this week.
I haven't welded in many years (since we built the roll cage for the rally car we ran for a few years) either but it's so easy and a hell of a lot of fun. Clean, ground and go. Just make sure you tack the whole thing together and when welding a tube, weld the whole thing at once. Don't weld one side and let it cool without doing the other side.
Here's the progress as of last night. I went with the vertical supports centered between cross braces simply because I wanted two posts to use as mounting locations for the gas piping. Before I had any of them welded in, I stood on the thing and jumped. The steel didn't move AT ALL. I WAS going to weld in just one, middle support and actually had the frame prepped but then stopped because of the gas piping.
Another addition: Little Chugger pump #2.