There are sometimes as many as six author appearances a week at Murder by the Book. That's reason enough to love it. Add that the store specializing in mysteries has an ­extensive range of titles and an incredibly knowledgeable staff, and it's easy to see why it wins our Best Bookstore award. Authors ­routinely alter their tour plans to stop at Murder by the Book, which they say is among the most hospitable in the country (read: they sell a lot of books). So, want a graphic thriller? Murder by the Book has it. How about a steamy whodunit? Got it. Or an English cozy? Check. Mysteries — with every level of intrigue, sex and violence, and characters ranging from the hardened P.I. to the English grandma, the ­modern vampire to the medieval damsel — cram the shelves.