Here is another project he helped me with almost two years ago and the house is still standing (knock on wood!!!). LOL
http://forum.polkaudio.com/discussion/c ... nt_1717848
Guidelines for a professional install (not necessarily complete!):
0. Pull permit from local jurisdiction.
1. The L6-30 receptacle you linked to is fine. I would mount it in a metal box with metal faceplate. I would personally use a 4x4 box for the extra room.
2. You should be using 10 GA wire for a 30A circuit. You can use NM-B (aka romex) which you can get with 2 HOTs and a ground. It will be called "10-2 NM-B". The 10 is the wire gauge, 2 is number of current carrying conductors. It will have an appropriately sized ground (10 GA in this case). Note that if the romex will not be covered by drywall, you can not use it. Romex is only rated for use where people are not able to touch it. In which cause you must use conduit and individually stranded wire.
3. Make sure your metal box is grounded.
4. You will need a double pole 30A circuit breaker appropriate for your panel. I hope it goes without saying that you should cut power to the panel before working on it!
5. Get work inspected by your local inspector.