Here you should visit this site for a lot, Google Hacking Database (GHDB) in here > http://johnny.ihackstuff.com/index.php?module=prodreviews this will help you to search for warez, like a real warez d00dz =)

Here is some of my research on google:

lets use filetype:

filetype:iso iso
filetype:rar rar

ok, if you want to use some thing specific, try this

site:microsoft.com filetype:iso


Check this site also for more file extensions (filetypes):
http://filext.com/index.php


There is a lot what you can do with google just use your imagination, my friends!