iTunes Consolidator is an easy to use application for locating songs that have been removed from your iTunes Library. Have you ever deleted a song from iTunes but clicked "Keep Files" in iTunes? iTunes Consolidator finds those files and gives you the chance to change your mind.
DRDUL The idea sounds great in principle, but I couldn't get it to work. I launched the app, clicked the OK button at the prompt where it tells me it's running in demo mode, and then it froze. I had to force-quit. I tried it again with the same result, so I dragged it to the trash. (Version 1.7)