My QW button fell off, I don't have insurance on my BB, how do I go about getting a replacement key or getting the phone repaired.

Call TMo first, for a warranty replacement if they will. I honestly don't know about missing QWs. (If you purchased it from TMo).

ive seen keypads for sale on ebay!

Here is a place to get keypads. However, I'd try getting it replaced under warranty by TMo first. If, for some reason, they won't cover it then this might be your ticket.

Cellular Accessories - SonyEricsson, NEC, Motorola, Nokia, Panasonic, Sanyo and Samsung. Quality housing, keypads, LCD screens, chargers, batteries, data cables, parts

I think T-Mo will replace it for you as long as you are within the year... They will however check it to make sure it's not user damage and if the water sensor has been activated they will charge you $100..... Also when it's replaced you will get a refurbished unit...