Well, the first book that immediately comes to mind is The Goddess Companion by Patricia Monaghan. I love its daily pieces of poetry or song, and the few paragraphs about each. It draws from all religions, and it's just lovely. My review is here.
Next would be the Corpus Hermeticum. I need to re-read it, it's been a while.
I am also a pretty big fan of the Tao Te Ching.
I've also enjoyed Ceisiwr Serith's A Book of Pagan Prayer and A Pagan Ritual Prayer Book. Both have pretty wonderful prayers in them that have inspired me to write some of my own. More detailed reviews here and here.
One book I need to find a copy of and finish reading, because I had to turn it into the library back home before I was finished, is Women of the Golden Dawn: Rebels and Priestesses: Maud Gonne, Moina Bergson Mathers, Annie Horniman, Florence Farr by Mary K. Greer. It was really interesting, what I got to read of it.
I actually have a wishlist here on Amazon of pagan-ish books I want. That's my pagan/goddess list, but I also have an astrology/philosophy list here.
For a full list of witchy books I own/have read, check out the Witchy Books page at the top of the sidebar on the right. Or follow this link.