Dead run / P.J. Tracy.

Enhanced descriptions from Syndetics:

The overwhelming response to Live Bait proved P. J. Tracy's second novel was no fluke. The Chicago Tribunesaid it best: "Tracy is a writer who can walk that thin line between humor and serious crime without sacrificing the needs of either side." For fans craving electric suspense, high-energy banter, and intricate plotting, the wait is over: Dead Run has arrived. Monkeewrench founders Grace MacBride and Annie Belinsky, along with Deputy Sharon Mueller, are driving from Minneapolis to Green Bay, Wisconsin, where they believe a new serial killer is just warming up, when their car breaks down, deep in the northern woods, far away from civilization and cell towers. A walk through the forest leads them to the crossroads town of Four Corners, where they had hoped to find a landline and a mechanic, but instead find . . . absolutely nothing. Something terrible has happened in Four Corners, and the complete absence of life and severed phone lines in every building make it impossible to get help. Grace, her senses honed by a lifetime of justifiable paranoia, sees the sinister in every detail, and her intuition barely saves all three of them when they witness a horrifying double murder. Grace, Annie, and Sharon are suddenly running for their lives, while the rest of the Monkeewrench crew, along with Minneapolis cops Leo Magozzi and Gino Rolseth, strike out on a blind search to find them.