Before you use any resource, always make sure you check the usage rights so that you understand the limitations of each agreement.
Triple Scoop Music - a fairly large collection of great music from around thet globe, including popular musicians and grammy winning artists.
Stock 20 - search by genre, latest upload, or even featured artists
Red Beard Music - a site for more popular music artists to offer their music for a limited annual license at a very reasonable price.
StockMusic.net - searchable database of royalty free music, available by individual download or as a discounted set
Pump Audio - from Getty Images comes great artists and music for purchase and download
Royalty Free Music - subscribe, download tracks, or buy a CD of royalty free music
ShowIT Music - David Jay is passionate about finding and offering cool music that is royalty-free for photographers and videographers to use professionally
Soundtrack Arcade - a growing archive of royalty free music for a variety of genres
Granite Audio Pro - dedicated to professionally composed royalty free music for photographers and videographers
Music Bakery - a one time subscription with unlimited downloads
TrueTone Productions - pay per song acoustic instrumental tracks
PD Info - royalty free music library arranged by genre and ideal uses
Pod Safe Music Network - one of the largest collections of creative commons liscense music and artists
Pod Safe Audio - unsigned artists share their music for download