Well, even ignoring Kazaa, that lovely file sharing service thats based on a privately owned island outside of the US Laws which shut down Napster and Audiogalaxy... theres The CD Database... CDDB.
Found at:
http://www.gracenote.com/music/Just type in "Salt-n-pepa" (The three girls had a funny way of hyphenating their name) and "Push it" for the track title, and you'll get all sorts of suggested albums that the track features on.
Type in "NOW" into the Album name and you get such things as "NOw 12" which is where I play "Push it" from, whenever I want something that'll mix in nicely with "Pink: Get this party started".