Horseman (The Hollow Book 1) by Christopher Golden and Ford Lytle Gilmore

Following the death of their mother, Aimee and Shane move with their father from Boston to the small town of Sleepy Hollow, NY where their mother had family roots. From the moment they cross the town lines, however, strange things begin to happen. Soon sightings of a large black dog, a mysterious headless man on a horse, and a talking tree are reported. Strange sightings, however, are followed by gruesome attacks and murders. Aimee, Shane and their new friend Stacia after witnessing some of the oddness decide to investigate what is going on themselves, as none of the adults are willing to accept a supernatural explanation. The teens begin to piece together the puzzle using historical documents and Washington Irving's novel. A very creepy look at a familiar tale. Definitely not a book to read after dark! A great start to a new series that will have horror fans anxiously awaiting the next installments. Underage drinking and sexual references may make this inappropriate for some readers.