If your work here at EUSD ever requires legal sound effects for some multi-media project, we have access to a large, 10-volume collection from Sony Pictures. You'll have to take a trip down to the Carolyn Gilbert Education Center (in the Technology and Media area)to get the effects you need, but it's free, legal, and high quality.
If you want to preview what's in the collection, you can see the entire contents here:
There is also a little tutorial on how to easily find the sound effect you need quickly (they've been loaded into iTunes on the one machine they are loaded onto for easy searching).