Tobi Sapphos
The Only Astrology Book You'll Ever Need by Joanna martine Woolfolk really is a fact filled interesting book. It basically is one of the best books you'll find for astrology.
That's a great book, and really helps when you're first learning how to construct a Western Natal Chart.
Right now I'm reading/studying The Complete Astrological Handbook for the Twenty-first Century, it has information on Chinese, Tibetan, Vedic, Arabian, Judaic & Western Astrology. (ISBN is 0805210865, in case you're interested) I would highly recommend this book for those of you that would like to learn about Vedic Astrology.