The best all-around travel/guide book to Azerbaijan is written by Mark Elliott, entitled simply "Azerbaijan", and published by Trailblazer (latest edition in 2004, I believe). It is simply your best resource for the country, except of course for more specialized academic / historic books. You will find listings on even the smallest village, with a hand-drawn map of that village!
You will particularly like the map of Xinaliq, with the indication "old men", where indeed (many tourist can confirm) - two old men were to be found, sitting and staring at the mountains in the distance! This book is truly a labour of love, from someone who obviously has become totally fascinated by this country, its people and its history. Even if you're not going there, you'll enjoy the read.
Otherwise, you might want to read the famous novel "Ali and Nino", by Kurban Said, kind of a Georgian-Azerbaijan version of Romeo and Juliet, written in the early portion of th XXth century. Very evocative and nicely written. And for the even more incredible story of its author, read the recent biography of Lev Nessinbaum (a.k.a. Kurban Said), entitled "The Orientalist". It came out in 2005 - a fascinating book. The LP guide to Armenia / Georgia / Azerbaijan is also okay, although nowhere near as satisfying as the Elliott guide.
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