This guy has a lot of information and photos on Costa Maya. He has been on A LOT of cruises and post a lot of trip reports and good photos. After you look at the link below, go back to his home page and check out his other trips.
We have been to Costa Maya a couple of times before Hurricane Dean. The place we walked to was wiped out. We are now booked on a Carnival Cruise for Nov. this year out of Mobile, AL. We will take a Carnival Excursion to a beach. They have one for around $40.00 a person that includes transportation and open bar.
We dont do a lot of site seeing, we are beach people. (Funny, we live near Gulf Shores and Pensacola Beach and go all the time here, but we still love the Beaches in the Caribbean!)