Disinfopedia - Collaborative project to produce a directory of public relations firms, think tanks, industry-funded organisations, and industry-friendly experts that work to influence public opinion and public policy on behalf of corporations, governments and special interests.
Psychological Operations Field Manual No.33-1 - Excerpt from the 1979 by Department of the Army Headquarters in Washington D.C. publication addressing various propaganda techniques.
Wikipedia: Propaganda - Hyperlinked article about propaganda, a specific type of message presentation aimed at serving an agenda.