OK, this is kinda gimmicky, but I was impressed with the technology-- SongTapper.com.
Seriously. You tap the lyrics/syllables of a song you have stuck in your head on teh spacebar, and it comes back with the closest matching songs. Now, Ihave no sense of rhythm, beat, or music in the slightest sense, but it identified all 3 songs I tested it with. I was impressed, to say the least, considering my ineptitude.
Try it out.