Go to songbpm.com and enter an artist and title. SongBPM will search its database and return all songs that match, along with the beats per minute (BPM) for each song.
As an example, if you type Nirvana and Smells Like, you’ll get several versions of Smells Like Teen Spirit.
I expect a future version of iTunes to do this, too. Maybe by linking to that website like they do with CDDB. iTunes should have done this all along.
Handy
No matches for Dream Theater’s “Dance of Eternity.” I guess no other song has 100+ time signature change sin about 6 minutes or so.