I'm convinced that the generation of kids I see in my classroom today are the ones who are actually going to DO SOMETHING about environmental issues. Here are some links that I think will get you started.
http://www.davidsuzuki.org/
http://www.treehugger.com
http://www.idealbite.com
http://www.stopglobalwarming.com
http://www.grist.org
http://www.gocarbonzero.org
http://www.myfootprint.org
http://www.earthday.com
Visit this website first, then go see the movie "An Inconvenient Truth." http://www.climatecrisis.net/
Here's a great link if you'd like to do some shopping. Seriously--it supports fair trade, organic, environmentally friendly products. http://www.taraluna.com