University of Pittsburgh
U of Pitt: Medieval Mont Saint Michael
A great site for photos inside and out of Mont Saint Michael. You will also get a map with the location of the Mont marked. Also, there is a great page with plans and drawings of Mont Saint Michael.
Catholic Online
Catholic Online: St. Michael the Archangel
Archangel Michael is the name sake to Mont Saint Michael. This page gives you a brief description of who Archangel Michael is.
Other
Mont St. Michel / Webfoot
This site talks about the geography of the Mont and its architectural history.