Lawn Mower Engine Repair Guide

I was searching around the internet for how to's on fixing lawn mower engines. Specifically a old Briggs V Twin engine. I came across this guide for $20 called Lawn Mower Made Simple - Small Engine Repair Guide and EBook. I have read a lot of good reviews on this. Has anyone used this personally? Or maybe you can recommend a book for me? I am trying to learn all the basic repairs for my lawn mower. Thanks