Recommended books:

Basic Astrology
The Everything Astrology Book by Trish MacGregor
Parkers Astrology by Julia and Derek Parker
Planets In Transit by Robert Hand
The Twelve Houses by Howard Sasportas

Predictive Astrology
Predicting Events With Astrology by Celeste Teal
Identifying Planetary Triggers by Celeste Teal
The New Solar Return Book Of Prediction by Raymond Merriman
The Art Of Predictive Astrology by Carol Rushman  

Medical Astrology
Astrological Timing of Critical Illness by Noel Tyl
An Astrological Comparison of Planets In Medical Diagnosis by Beverley Rostant
Signs Of Mental Illness by Mitchell E. Gibson M.D.