I ran across SoundSnap today – what a great resource for finding free sound effects and music loops. For those participating in the GGMUG Silverlight Game Development Contest, this might come in handy for you, so please check it out!
http://www.soundsnap.com/
By the way, the GGMUG is a great venue to meet new people who are passionate about .NET development. If you live on the East side of town, and just can’t make it to those Alpharetta meetings held by the other user groups, then please check this new group out if you haven’t already.