Last year my sister recommended Mark Driscoll's 4-part lecture on spiritual warfare. I learned a great deal from it. I'll embed the audio only, but there is video from Mars Hill Church if you want to watch.
They're intense but understandable. Driscoll warns against dabbling in this stuff before you get a good handle on what is at stake. Remember the 7 sons of Sceva from Acts 19:11-17!
