Where can I find video lectures online for graph theory / small world networks or any other similar topic?

There are many lectures available on YouTube. Granted, the quality there varies, but I’ve found some top-notch stuff.

While don’t think it has those particular topics yet, Khan Academy is quickly expanding, and those are the kinds of things I would expect to show up there. This is an excellent resource for quality video lectures.

Have you tried iTunesU? Bunch of free lectures there on a huge number of topics.

http://www.openculture.com/

Not sure if this specific topic is on, but you might find a link somewhere.

Small Worlds Network

Pick your poison.