The book is Magic Bites. There's a sequel coming out next March called Magic Burns. I've not read the book yet, but it's on my TBR pile. I have heard some good things about it, though.
Here's a brief blurb on Amazon, along with a recommendation by Patty! Hmm, I might have to move that up the TBR pile.
Patricia Briggs
Splendid...an edgy dark fantasy touched with just the right amount of humor.
Book Description
Mercenary Kate Daniels cleans up urban problems of a paranormal kind. But her latest prey, a pack of undead warriors, presents her greatest challenge.