How do I find where an environmental variable got set?

I installed a program to try it out, and decided I didn't like it so I moved the app to the trash. Today, in my shell, I noticed that there are a couple of PROGRAMNAME_BLAHBLAH environmental variables set. I'd like to remove those, too. I don't even have a .bashrc or .bash_login, so I grepped every file I could think of (~/.* ~/Library/* /Library/* /etc/*). The only place these variables turned up was a file ~/.MacOSX/environment.plist, so I removed it from there (Xcode can edit binary plists), but new shells still have these variables set. What other files does Mac OS X 10.7's terminal/bash run on startup? How might these variables get set? Or is it something funny like "need to reboot after editing environment.plist"?