I am planning on taking the CFI plunge before the end of the month as well.
I have been writing lesson plans from the GLEIM "red book" Flight Instructor Flight Maneuvers. The title suggests it is only flight maneuvers, but in fact it covers every CFI PTS item. It might run you 15-20 bucks.
I make a basic lesson off of this book and then refer to the Airplane flying handbook, Pilots handbook of aeronautical knowledge and other various sources. I feel that covers all of the bases.
Hope that helps! Tell us how the checkride goes!
Good LUCK!