The Vampire Killers by Clifford L. Linedecker
If you are fascinated by real murders with a vampiric touch - this book is for you! It covers the story behind the so called Kentucky Vampire Clan with Rod Ferrell as it´s leader.
The Science of Vampires by Katherine Ramsland
Katherine Ramsland is a professor in forensic psychology. She has written several non-fiction books about vampires and serial killers. In The Science of Vampires, she explores the facts behind the myths.