Mercy Thompson is a 13-book series with 13 released primary works first released in 2006 with contributions by Patricia Briggs.
Mercedes is Volkswagen mechanic living in the Tri-Cities area of Washington. Her Native American heritage has somehow given her the ability to take the form of a coyote at will. She's surrounded by far more powerful supernatural beings, including werewolves, vampires and an assortment of fae.