If you're interested in an inexpensive (i.e. $8USD) map of Cancun (in English!), take a look at [mapchick.com
This appears to be a small business in Iowa, that mails out maps on request, and trusts people to pay them on the honor system. (What a concept!)
I like to know where I'm going, and I usually find maps on the Internet, but this printed map provides a level of detail that unattainable on a letter-sized page. FYI, the Westin Cancun is almost as far south in the peninsula that you can go (except for the Club Med). The restaurants all appear to be towards the north end of the peninsula.