The Pew Center for Global Climate Change does analysis, governmental & business lobbying, and education about climate change. They are a great online resource for tutorials and news on the subject, somewhat like those fabulous scientists over at RealClimate. However, the Pew Center's primary target is policy, which I feel is the more important arena; the scientific community already knows what the basic problems are, but governments and businesses are still fighting about the most basic solutions. It's a US site, but has information from the state level to the international level, and a whole page on "businesses leading the way." (Though some of the businesses there list pretty candy-ass targets, or no targets at all. ...But I suppose the first step is getting these giant firms to even start thinking about climate change.)

It appears that the Pew Center for Global Climate Change is part of a constellation of institutions founded by The Pew Charitable Trusts. These trusts include several other great policy organizations dealing with everything from nanotech to alcohol advertising to election reform; they also include many informational organizations, from to stateline.org (a state-by-state political news site).