This book has definite pros and cons for me. First, let me say that I consider myself an early intermediate player, having previously worked through Fingerstyle Guitar by Ken Perlman (http://www.amazon.com/Fingerstyle-Guitar-Ken-Perlman/dp/157424115X), which I did under the guidance of the same teacher that I have started working through this book with.
The book is organized into two sections: first, an instructional section, with exercises and small training pieces; second, the tabbed songs.
The instructional section is pretty good, but I was dismayed to discover that there is no accompanying CD with the book (hearing the examples would have been great...fortunately, I have a good teacher). Alas, the instruction pretty much stops once you get to the songs. The selection of songs is great; lots of really fantastic material, much of which I hadn't heard before. Each artist is given a paragraph or two of introduction, along with some background on the songs. However, there is virtually no instruction on actually playing the songs (fingering recommendations or slide technique, etc.). It's just you and the tab from there on out.
Fortunately, every single song is available on iTunes; still it would have been nice to have a CD included, first with the original recordings and second with a recording of the music (as tabbed out) being played. Since the originals are often quite old, those recordings are not as helpful as they might be in some cases. Further, the originals are often more than a single guitar (even the very first tune, Black Ace, has a strummed accompaniment in the original, so the tabbed version sounds a bit different). Overall, however, this isn't a big deal.
Also, it should be noted that most of the songs have tab for just a couple of variations played in the original recording. This is not unexpected, and can provide good training for the student (figuring out new variations), however in some cases the author was a bit chaotic in his choices for what to tab and what not to. Example, Yo Yo Blues has an Introduction, verse 1, verse 2 and a variation of verse tabbed out, spanning five pages in the book; yet Tampa Red's You Got To Reap What You Sow has two small sections (main and a variation, although it isn't marked as such) with a small coda, on only two pages. Listen to the two originals! Yo Yo Blues is pretty much the same throughout (minor differences) yet You Got To Reap What You Sow is full of variations, and has a neat little intro that, while not terribly complicated, isn't tabbed out at all! The latter tune is far more deserving of the extra attention than the former, IMHO (although I like both).
The worst part about the book, however, are the errors. While I have only looked at a handful of the songs in detail thus far, so far almost all of the ones I have attempted have had errors in the tab -- mostly subtle, but some pretty bad. So, again, not having a more experienced player to go through it with you -- my teacher has been invaluable here -- would make it very difficult. Having said that, the process of going through the songs, finding and fixing errors, has itself been very educational (good ear training). Like most things, you get out of it what you put in...
Finally, I would say that the songs are not necessarily well-ordered, in terms of difficulty. Black Ace is a good one to start with, for sure, but I felt that song two (Milk Cow Blues; the Kokomo Arnold version, which I was not familiar with, and is much better than the Robert Johnson version) was significantly harder. So much so that we started skipping around after that (e.g., song four, Yo Yo Blues, seemed much easier to me than Milk Cow; even the Tampa Red stuff was easier to get the basics, as it is slower and much less rhythmically challenging, although it is harder to really master in terms of tone and expression -- it's Tampa Red, after all -- but perhaps this is just personal ability).
Bottom line: I like the material a lot and I'm glad I have the book, but I wish there was a CD, more detailed playing notes on the songs themselves, and fewer errors in the tab. If you are experienced enough to work through some of these shortcomings, or have a teacher to help, the book will be great as you'll learn a lot doing so. If you are not so experienced and do not have help, I would be careful as you may get frustrated.