As you can see here, we've got a damaged hot shoe on this T2i (550D). A little bit of searching on eBay has yielded the part we need to replace. It's an entire assembly of the top cover.

You'll need the following:

Plastic opening tool

Small Screwdrivers

Pliers (or surgical clamps :D)

Tweezers

Pen and paper

Get the camera ready by removing the neck strap, battery, lens and SD card.