I didn't buy this book, but I did buy the Chord Progressions book (which was really good and that leads me to assume that the 101 book would be good too).
Considering the fact that book's only $9, I'd say give it a shot. If I'm not mistaken the guy who wrote it is a member of this board. I'd shoot him a message and ask him about it. He could probably give you a better idea of whether or not this book is right for you.