This book is a huge reference for all the common chords you might use on guitar. It has a ton of information and I anticipate I'll be using it for years.
The book is divided into sections by root note, C through B. Each note has subsections for the main chord qualities; major, minor and 7. Every chord is then laid out with a numbered diagram, as well as a photo showing the proper fingering position. It has several inversions for most chords.
To get an idea of the comprehensiveness, the first section (for note C) includes: Cmaj (5 inversions), Cmaj6 (5), Cmaj7 (5), Csus4 (2), Csus2 (3), Cmin (5), Cmin6 (2), Cmin7 (3), Cdom7 (5), C7#5 (2), C7sus4 (3), Cdom9 (1), C7#9 (1), C7b9 (1), C13 (2). That's a total of 15 chord types and 45 inversions just for C! The other 11 sections are similar.
My only complaint is the non-standard diagram notation (it's similar to the usual chord diagrams, but rotated at an angle and looks more like a photo than a drawing). This is probably a plus for novices, or people used to learning by watching someone play in front of them; for me it's an annoying mental adjustment. But it works, and is not a big enough gripe to knock off a star.
A final note: this book is also a trove for ukulelists (I play both). Since the intervals between the ukulele's strings are the same as the 4 treble strings on the guitar, all the chord shapes listed in the book will also work on the ukulele. (They'll have the same quality; major, minor, 7, etc.; but sound 5 frets higher in pitch, so a Cmaj7 on the guitar is an Fmaj7 on the ukulele. Baritone uke is easier still--even the note names stay the same as the guitar.) Just ignore the two bass strings, and strum away!
If you are a ukulelist, I'd also recommend Roy Sakuma's "Treasury of Ukulele Chords", which is available on Amazon too. Happy playing!