The Mexico Tourism Board (tel. 800/446-3942; www.visitmexico.com) is an excellent source for general information; you can request brochures and get answers to the most common questions from the well-trained, knowledgeable staff. The tourism boards of Baja California (tel. 664/682-3367; www.discoverbajacalifornia.com) and Baja California Sur (tel. 612/124-0100; www.explorebajasur.com) have more Baja-specific information.
The following websites are useful: www.allaboutcabo.com, www.bajaquest.com, www.bajainsider.com, and www.rozinlapaz.com.