Originally Posted by dcrowell

I strongly recommend that you let the shop do it. Hopefully under warranty.

You'll need an new chain, chain tools, derailleur, derailleur hanger tool. The derailleur hangar tool is a big bar of metal with a bold on the end. It gives you the proper leverage to bend the derailleur hangar back in place. You don't want to bend it multiple times, even steel will break eventually.