The Diana Tregarde Investigations are a trilogy of books by Mercedes Lackey that were intended to be more than just a series of 3, but some psycho fans scared her & the cash she made from the series wasn't enough to keep writing the series, which is quite a tragedy. The series centers around Diana Tregarde, who solves the 3 cases in the series using magic, brains, & wit. It sounds wacky, I know, but the series is VERY GOOD... "Children Of The Night" was a vampire story without the expected trappings and some *gasp* actual scares!!! I was hooked right there... & if that isn't enough for you, there was even a blurb on the book from Stephen King saying that Mercede's books would keep you up long after bed time; I figure he knows what he's talking about.
CHILDREN OF THE NIGHT
BURNING WATER
JINX HIGH
There are also some short stories to be had though I haven't read them.