There is a nice supermarket in Puerto Morelos as well as the pharmacy.
The supermarket has large variety of sun lotions, food and drink, stemps for your postcards they also have huge variety of the buttons if you need one ( see pictures!!!!!!!!!!!).
The HSBC ATM (bankomat) is right next to the supermarket.
In the pharmacy you can get mosquito repellant, as well as all the meds (they have allergy meds too). You can also get there calling cards as there is a phone outside. We called US with no problem.
You can also take a drive to the Centro Maya in Playa del Carmen. It is a Mall where you can find all you need. Food, towels, umbrellas, beach chairs, plasma TV, new car... etc.
There is also a book store in Puerto Morelos, where we got our map for $6 as well as reliable information about driving around and the distances.
What to buy: See our pictures
Puerto Morelos is really small but it does have a few small shops near the town square. We purchased this beautiful woolen Mexican blanket for just a few pesos.
What to pay: The prices here in Puerto Morelos are much lower than those in Cancun. Most of the shops will accept dollars in lieu of pesos. Just be ready to do the conversion in your head and to bargain the price down farther.