Chiang Mai is not as well covered with specific guidebooks as Bangkok. Of the major guidebook series, only Lonely Planet has a book dedicated to northern Thailand. It's worth noting that most hotels and many restaurants have free maps and tourist booklets freely available. There's no real need to purchase a map, although both the Nancy Chandler and Luxe maps have content you won't find elsewhere. Also be sure to see our own ebook guide to Chiang Mai.