Dr. David Suzuki is well-known in Canada as a scientist, environmentalist, and broadcaster. The David Suzuki Foundation works to "to find ways for society to live in balance with the natural world that sustains us." The website contains information about Sustainability, Oceans and Sustainable Fishing, and Climage Change and Clean Energy. Some of the information is Canada-focused, but it is generaly applicable to those in other countries as well.
On the What You Can Do page, there are links for actions that can be taken "At Home" and "At Work," as well as information about living a Carbon Neutral lifestyle.
This looks like a good resource for ideas about how we can make the necessary changes to meet the challenges of global warming and move toward a more sustainable society.