I was looking for some information to verify my answer to another post when I ran across a pretty cool site.

http://www.delmar.edu/Courses/

These are online courses at Del Mar College. Well, you are supposed to pay for the class and take it through the school, but they just happen to have all the information sitting right there on the web. So you may not get college credit, but you can still learn a lot. There are 9 courses there all dealing with networking in one way or another.