Avi Ariav has written a page with a nice selection of free pieces for Clarinet including duets, trios, quartets, and even wind band or orchestra arrangements.

A small site that mirrors much of the sheet music here at MusicEdMagic.com

A well designed sheet music site with lots of information on the sheet music that it provides.

Learn-and-Master-Guitar.Com is a non-biased review site. It takes a look at some of the web's more popular "learn to play guitar" programs.