Nightwalkers / P.T. Deutermann.

Enhanced descriptions from Syndetics:

Cam Richter, needing a break from his too-eventful detective career, is in search of more peaceful pastures in the North Carolina countryside. He buys a seven hundred acre ante-bellum plantation, but it doesn't take long for him to discover that his new locale is not as quiet as he'd hoped. Almost immediately, Cam finds himself caught up in mischievous pranks around his land, the site of a Civil War-era massacre. When the pranks turn hostile, however, he realizes he's been targeted by a killer who holds him responsible for something Cam is pretty sure he never did. As he tries to find out why someone wants him dead, he begins to uncover the secrets of his plantation and how the land's tragic history is still tangled up in the present. Cam will need all of his resources, including his redoubtable German shepherd companions, to stay alive as he deals with a determined stalker, some very eccentric people, and all the entanglements of a place suddenly alive with secrets and the fruits of a bloody past.