On the shores of Lake Atitlan are several small towns. Santa Cruz is one of the smaller of these towns. At water level there are a few hotels, restaurants and one large, active and very nice hostel. La Iguana Perdida ( the lost iguana) has much to offer. First I have to report that the Lonely Planet has this place all wrong. Local rumors (Guatemala has more rumors per capita than any other place on the planet) is that the writer for the Lonely Planet never actually visited the place due to some financial problems with the home office. The LP has reported through more than one issue that the Iguana has no hot water. I am pleased to give a personal report that the Iguana has hot showers and cold beer which fits my view of how life should be on the road.
The Iguana is almost a village itself. Dozens of room types to choose from - big dorms, small dorms, privates, cottages, etc. They have scuba lessons and gear + lots of hikes and other ways to interact with this beautiful place.
Also down at water level is the restaurant Jacaranda - great food on the water with a perfect ambience. The prices are very reasonable. Definitely worth your visit if you are on the lake.
However just visiting the Iguana and environs at lake level really isn't getting to see Santa Cruz. You should visit the church in the town square. It has dozens of carved figures that date back centuries. All lined up along one of the church walls makes you feel you are in an eternal procession.
The Amigos de Santa Cruz, a local non profit are building a new school that will have a commercial kitchen + local, historically accurate crafts store just off the square. I visited the place while still under construction and it will have the best view of the lake from any location. It is truely breath-taking. Check it out sometime in 2010.