These groups can be a good source of information. For others, you might want to look at Directory of Associations, which is a searchable list of over 36,000 associations worldwide.
The United States Government is a good source of data and other types of materials. Below are some of the most useful for environmental issues. See the Government Documents for essential resources in all areas of government.
Julie Chen, Librarian
Sorrells Engineering & Science Library, Wean Hall
EPP pages created by Sue Collins, maintained by Julie Chen