This is a search tip I picked up a while back :

If your looking for wav files or mp3s or avi files or anything really type this into a Google search page and...feast you eyes :

            ?intitle:index.of wav

You can change or adapt the WAV bit to :
           ?intitle:index.of wav drum
or        ?intitle:index.of wav guitar
or        ?intitle:index.of wav saxophone
or        ?intitle:index.of wav car
or        ?intitle:index.of wav water

Or you can make a totally different search :
           ?intitle:index.of mp3
or        ?intitle:index.of avi
or        ?intitle:index.of gif smile

If you play with this search command and understand it, it's an amazing tool for finding media files on line.

What your doing is looking for those "Index of..." pages, the ones you get when an online folder has no 'index.html' and displays only the contents of the folder.

The ?intitle:index.of wav search brings back about 590,000 results.......happy searching!