Other
Bureau of Reclamation: Nepa Handbook
This site from the Bureau of Reclamation provides the National Environmental Policy Act handbook for employees. It can be downloaded in sections. Attachment 1 has the policy regulations.
US Environmental Protection Agency
Epa: Summary of the National Environmental Policy Act
Use this site from the EPA as a portal to find the text of the National Environmental Policy Act, passed in 1969, as well as a history of the act.