Book 36 Dead Witch Walking by Kim Harrison
Rachel Morgan is a witch in 'modern day' Cincinnati - a genetically engineered virus killed half the world's human population forty years ago and revealed the existence of witches, werewolves, vampires, pixies, fairies, etc in the aftermath. She is in law enforcement chasing down supernatural criminals, but dissatisfaction with her role at the Inderland Runner Services leads her to leave and set up her own runner agency alongside a vampire and pixy. Trouble is, the IS don't just let people leave so she has to find a way pay off her contract with IS and get them to lift the contract they have on her life.
This one is a re-read but it has been a few years. Rachel is a bit annoyingly self-involved, but it's a good story, reasonably fast paced and the world created by Harrison is surprisingly normal in spite of the magic!