This book list is a few of my favorite essential oil books. 

This book list is in no way complete but is a great place to start.

Butterfly Miracles with Essential Oils
By LaRee Westover
(I wrote it so you would hope I would at least like it)

Healing Oils Of The Bible
by David Stewart

The Chemistry of Essential Oils
by David Stewart
(These are some of my absolute favorite books.
The Chemistry of Essential Oils goes very in depth into the different constituents of essential oils.)

The Fragrant Mind
By Valerie Ann Worwood

The Complete Book of Essential Oils and Aromatherapy
By Valerie Ann Worwood
(I love these books.  This author does a great job with the personality of oils.
However, I am not very fond of most of the blending recipes.)

Aromatherapy Workbook
by  Marcel Lavabre
(This is a great book about blending.  He knows what he is talking about.)

Aromatherapy For Healing The Spirit
By Gabriel Mojay
(This is a great book for studying the emotional side of essential oils.)