Wild Sign: Alpha and Omega Series, Book 6 (hardcover) Patricia Briggs
In the wilds of the Northern California mountains, all the inhabitants of a small town have gone missing. It's as if the people picked up and left their possessions behind. With a mystery on their hands and no jurisdiction on private property, the FBI dumps the whole problem in the lap of the land owner, Aspen Creek, Inc.--aka the business organization of the Marrok's pack.
Somehow, the pack of the Wolf Who Rules is connected to a group of vanished people. Werewolves Charles Cornick and Anna Latham are tasked with investigating, and soon find that a deserted town is the least of the challenges they face.
Death sings in the forest, and when it calls, Charles and Anna must answer. Something has awakened in the heart of the California mountains, something old and dangerous--and it has met werewolves before.