Royalty free background music, buyout music loops. You can listen to them online, purchase on a secure server and use as much as you like. Delivered by instant download, or on CD.
http://www.shockwave-sound.com/

FindSounds helps you search the web for sound effects in various audio formats, through a number of audio-related search criteria.
http://www.findsounds.com/

An audio database and library of sound effects and musical instruments samples.
http://www.soungle.com/