For those of you who don't know Kim Harrison, you are seriously being deprived of the most wonderful series ever.
The series is called The Hollows and it centers around the sacarstic Rachel Morgan. A witch who can kick **** and still come out looking hot.
Let me give you some background on the story before I give away a little of the first book.
It takes place in Cinncinati around the present. Give or take a few years. In this world, werewolves, fairies, witches, warlocks, vampires, pixies, elves, and demons all live among the humans. Of course, it wasn't always like that. About 40 years prior there was a deadly virus in genetically altered tomatoes that killed many humans. But when they realized that not all of the humans were dying, so people were suspicious and confused. The only thing they could do was come out to the human population and tell them that they aren't human.
First Book: Dead Witch Walking
Now, they refer to those who aren't human as Inderlanders. Rachel works for the I.S. Also known as Inderlander Security. They take care of wild vampires and reckless werewolves, along with the dark ley line witches. Rachel, of course, works there as a runner. She goes out and basically captures those wrong doers so they can't harm others.
Her boss starts giving her crappy assignments and getting her into trouble for the smallest details, so she wishes her way out of the job. Which isn't very good considering that she also took a pixy and their top runner with her. A vampire with her own hidden agenda. Now she has a huge bounty on her head and has to try and stay alive while running her own runner service.
After that book there is The Good, The Bad, The Undead; Every Which Way But Dead; Fistful of Charms; and For A Few Demons More.
Here is her site. :]
http://kimharrison.net/