Mike Rohde is a pretty special guy on the Internet. Mike came up with the idea of Sketchnoting and has been teaching his techniques for years. I use some of these techniques in preparation for court appearances. Mike explained Sketchnoting in MPU episode 120. (Mike also prepared all the illustrations in my Email Field Guide.)
Mike recently released the Sketchnote Workbook which gives further Sketechnote instruction and includes examples from Sketchnoters of various skills (your truly included) demonstrating how they use Sketchnoting in their daily lives.