polyglotinc,
Can you go to your spotlight search box and type in “Uninstall MyEclipse” and see where the app got put? Should work with Quicksilver too.
Or pop open Finder and go to Applications, they should be in there.
If they aren’t any of those places, to totally wipe out MyEclipse, just erase the dir that was created. That’s it (the install basically just does a structured unzip… no funky files anywhere).