The All Music Guide to Blues - over 6,000 CDs rated and reviiewed
This alphabetically arranged Lexicon helps readers to make sense of the dizzying list of blues artists who have contributed to thise body of music. The book is fairly broad and includes many crossover type bands (blues derivation of Rock, for example), with a brief history and list of essential recordings from each artist.
I expected the book to be somewhat more "readable" rather than a catalogue of artists; however, it is useful as the latter. You will not be disappointed with the volume, and you will probably pull it out frequently when shopping for blues music, reviewing artists heard on public radio's blues shows, or when browsing the internet for non-copyrighted blues recordings (many of the oldest recordings are in public domain).
The price also makes it worthwhile. If it guides you toward a single, more satisfying blues recording (or helps you avoid a single stinker), then it's paid for itself.