I've been getting a steady stream of inquiries about Puerto Morelos, I imagine thanks to the relatively small number of web resources about this town. Here's a little FAQ - you can e-mail me if you have further questions, and I'll put the answers up here. I'll be happy too to put up any P.M. links that are brought to my attention.
Hotel La Hacienda has a web page, but I'm not familiar enough with it to give it a positive or negative recommendation. I did eat at their restaurant once last year, and was favourably impressed.
In the main square is a grocery store, currency exchange stands, a travel agency, souvenir shops, local artisans' craft shops and even an English-language bookshop. If you get bored, Puerto Morelos is an excellent base of operations for exploring the coast. There's the touristy shops and nightlife of Cancun a half hour to the north, countless spectacular beaches within an hour or two's drive to the south, the seaside Mayan ruins of Tulum (2 hours), the pyramids at Coba (2.5 hours), and further afield the world's best diving on the island of Cozumel (1-3 hours depending on which ferry you take from where), and Chichen Itza (a pleasant day trip by bus).