Shadow of the Wind by Carlos Ruiz Zafon by is an incredible novel, although it isn't really a full on horror novel. It's kind of a romance/mystery/gothic/horror hybrid. It does not feature werewolfs but its quite the modern classic if you haven't already read it. It follows the story of Daniel throughout his early life as he unravels the mystery of Julian Carax, an author who wrote the first book he had ever been engaged by.