Databases for Creative Commons and Public Domain Audio
If you plan to publish your audio piece, you should only use music and sounds that are in the public domain or published under a Creative Commons license (or that you create yourself). The list below, courtesy of the UM Podcasting and Audio Storytelling Resource Guide, contains some of the most common sound libraries used by audio creators.
More Online Sound Archives — may not be public domain. Check specific sites for copyright details.
PennSound Archive of poetry readings (alphabetical index by author)
UbuWeb sound archive (extensive avant garde arts archive)
Internet Archive: Audio (a vast resource for archival audio of all kinds—historic radio, music, ethnomusicological field recordings, audiobooks... incredible!)