I read a lot of vampire romances (seriously, a lot), and it is hard for me to choose one favorite. One of my absolute favorites, though, would be Halfway to the Grave by Jeaniene Frost. The main characters, Cat, a half-vampire out for revenge, and Bones, a vampire bounty hunter, are a great couple and the plot is a good mix of romance and suspense. Their story continues in three more books (so far), and is one of the best series in paranormal romance. Check it out!