The University of Illinois Water Gardening site has detailed instructions for making and maintaining a garden, storing plants in winter, and handling algae problems, as well as helpful illustrations on installing different types of plants.
Container Water Gardens
Water Gardening In Containers: Small Ponds Indoors & Out, by Helen Nash and C. Greg Speichert (Sterling Publishing, 1999; $14.95) provides inspiration and practical advice for making a container water garden. It covers different types of containers, plants, fish, pumps, and more. It's worth a look if you want to start small. Speichert is publisher of Water Gardening magazine.