Here are a few good books to get you started

Crystal Bible - Judy Hall
Encyclopaedia of Crystals - Judy Hall
Healing Crystals - The A-Z of 430 Gemstones - Michael Gienger
Crystal Therapy - How to Empower Your Life with Crystal Energy - Doreen Virtue
The Book of Stones - Who are they and What they teach - Robert Simmons & Naisha Ahsian