I am currently reading Iron Kissed by Patricia Briggs. This is the third book in the Mercy Thompson series.
Here is the summary from the back cover:
I could smell her fear, and it satisfied something deep inside me that had been writhing under her cool, superior gaze. I curled my upper lip so she could get a good look at my sharp teeth. I might only weigh thirty or so pounds in my coyote shape, but I was a predator...
Mechanic Mercy Thompson can shift her shape - but not her loyalty. When her former boss and mentor is arrested for murder and left to rot behind bars by his own kind, it's up to Mercy to clear his name, whether he wants her to or not.
Mercy's loyalty is under pressure from other directions, too. Werewolves are not known for their patience, and if Mercy can't decide between the two she cares for, Sam and Adam may make the choice for her...