Like me are you looking to become a more sophisticated Markdown user? You might want to checkout MacSparky’s Markdown Fieldguide. Only 10 bucks!
Markdown started as a clever way to write for the web but has become so much more. This book demystifies Markdown, making it easy for anybody to learn. This book includes 130 pages and 27 screencasts totaling more than one and a half hours of video. There is also an additional hour of audio interviews. This book will take you from zero knowledge of Markdown to being a Markdown pro and change the way you write for the better.
I’ll be checking out the PDF version since I’m a Kindle Store sucke… err, fan.
Update: Decided to go with the iBookstore version just for a little variety.