As I have said in the thread I just started on the subject, "The Tarot: History, Symbolism & Divination" by Place pretty much sez it ALL - clearly & to-the-point, but also, he gets to the very bottom of the many myths associated with the cards. It has more truth in it than any other book I've read page for page, all in 1 "place" (haha). It's at the very top of my recommendation!!
I'm with Danubhe . . . "The Tarot: History, Symbolism & Divination" by Robert Place is THE tarot book to have. So clearly written, insightful, intelligent, and helpful.
well ... if I could only save one Tarot book from the flames it would be Caitlin and John Matthews' Hallowquest: An Arthurian Tarot Course because it would be so hard to replace.
But if you ask me which books I refer to most often, it would come down to The Book of Thoth and Gareth Knight's Magical World of the Tarot. With Place's book coming up close behind.