MusicBiatch
Looks for MP3 music stored or hosted in various file sharing and uploading websites.
Seekasong.com
Facilitates MP3 searches and provides links to free downloads of MP3 files from all over the world.
SkreemR
MP3 search engine specializing in DRM-free music, podcasts, and speeches.
Song Crawler
Online music meta search service that makes use of eleven different MP3 search engines.