Hey
There's a short but applicable list of appropriate titles
here at Tarotpedia.com.:
Doane, Doris Blending Astrology, Numerology and Tarot, 1997 ISBN 086690462X
Hasbrouck, Muriel Tarot and Astrology: The Pursuit of Destiny 1986 ISBN 0892811218
Hazel, Elizabeth Tarot Decoded: Understanding and Using Dignities and Correspondences, 2004 ISBN 1578633028
Muchery, Georges Astrological Tarot, 1989 ISBN 0517682591
Thierens, A.E. Astrology & the Tarot, 1975 ISBN 0878770313
I'd recommend Hazel's book particularly. Also, I remember Teresa Michelsen mentioning back in April that she's working on a Tarot/Astrology text, but I don't think she's finished it yet...
Scion