Just wondering if this is a "pivoting" window as in you can open and shut it??? If its a fixed glass window, they are usually bonded to the body with a urethane sealant (like the front windscreen) It can be done, but its a major pain in the ass. If you have a mate thats done it before, call em in. I have done one meself before, and I'll be farked if i do it again. Askin the wreckers is sometimes a good idea, as those blokes will sometimes do cashies for ya. also look at:
http://www.autobodytoolmart.com/dent9.html. Remember it never hurts to have a go, and if ya stuff it, at least you can argue with the glass mob for a discount as you've already removed al the old glass