http://www.theecologist.org/  
This website is edited by the Resurgence Trust in the UK and has developed out of The Ecologist journal and then magazine. The website contains links to many articles of interest to those involved in the wider Green movement.

http://www.resurgence.org/magazine/
This is the website of the Resurgence and Ecologist magazine which is the successor to the original The Ecologist.

http://www.tandfonline.com/loi/fenp20
This is home page for Environmental Politics which is the leading academic journal that publishes academic research into all aspects of Green politics including Green thought, Green policy and Green movements.

http://www.earthfirst.org/about.htm
This is the home page of Earth First! Worldwide which is the direct descendant of the type of activism proposed by Deep Ecology advocates.

http://www.greenpeace.org/international/en/about/
Greenpeace is perhaps one of the most well- known environmental NGOs.