Well, you are going to want faucets, shanks, tails, tail nuts, washers for the tail, beer line, clamps (i don't trust just the barbs, maybe you don't need these),maybe a drip tray, liquid ball lock connectors, gas ball lock connectors, gas line (can just be more beer line), manifold with check valves and probably shutoff valves. I might be forgetting some other stuff too
Some good places to start are
northernbrewer.com,
austinhomebrew.com