Nancy Zingrone provides a nice annotated list (reachable here) of 36 basic books on parapsychology covering the history and evidence of this field.
Another book to consider: The Spirit of Dr. Bindelof: The Enigma of Séance Phenomena by Rosemarie Pilkington, PhD. You can read about it here, including a sample chapter. Warning, this book is likely to push your boggle threshold. But I know Rosemarie, and I know she's meticulous about her facts, so prepare to be boggled.