The Weaponer — Eric S. Brown

Long after the fall of man, humanity lives sheltered behind a massive wall that encloses the United States' last survivors of civilization. Outside the wall, the undead rule the world. Generations have passed and mankind has returned to the technology and life of the Old West, surviving off the land and doing what they can to get by. Hyattsburg, a haven once thought safe behind the wall, has visitors: hungry zombies. When an entire family is murdered and partially eaten, Alan, the world's last remaining Weaponer, is called to duty to aid those struggling to remain safe, as well as find out what happened and if the dead are the only ones to blame for the grisly deaths of innocents. Terror and zombies rule an Old West Apocalypse in The Weaponer.