MusicBrainz - A community-maintained open source database and encyclopedia of music information.
Mp3Bear - Mp3Bear is an Mp3 music search engine that locates the mp3 files all over the net.
Discogs - Discover music on Discogs, the largest online music database. Buy and sell music with collectors in the Marketplace.
MP3Juices - MP3Juices is a free mp3 search engine and tool that allows you to download unlimited mp3 files anywhere around the world.
AllMusic - AllMusic.
LoudTronix - LoudTronix is the most leading service that helps you to find and download your favorite Mp3 music without any limitation.