Tour of Biomes
Developed by the Center for Educational Technologies in conjunction with Wheeling Jesuit University and NASA's Classroom of the Future. Excellent site- easy to use format with great information. Nicely organized.
WorldBiomes.com is a site covering 5 of the major world biomes. This reviewed site provides you with various sub-divisions and examples of the 5 types of biomes and their distinguishing features.
World's Biomes -- From University of California at Berkley, this is an introduction to the major biomes on Earth.
Biomes of the World: -- From Radford University, Department of Geospatial Science
World Biomes (Kids Do Ecology): Not just for kids!
PBS Learning - Biomes: From PBS, click on "launch" to explore various biomes.