The Shadow Stone — Richard Baker

Accosted by bullies on a forest trail, Aeron had no way of knowing that the confrontation would change his life forever. Accused of a crime for which he bears no blame, he is pursued deep into the forests of the Maerchwood. First rescued, and then tutored, by the mysterious Storm Walker, he discovers a previously undreamed-of talent for magic, and his life is swept up in the study of the arcane arts .. .

. . until the very principles of magic, and indeed the future of Faeran, come under attack from the unspeakably evil influences of .. . The Shadow Stone