Check out these awesome instructional video clips that B&H has been posting on their web site. They are somewhat product driven but it is a great place to go and watch some instructional direction if you are in the market for purchasing anything from lights, cameras, video or audio. I also really enjoyed this article on unique ways journalists are adapting to the limitations in the audio track for the Canon 5D Mark II. A very thorough review of multiple on-board mic systems for that camera.