Communication Studies & Social SciencesCommunication Studies & Social Sciences
Academy of Motion Picture Arts and Sciences (USA) 
Broadcast Media
Academy of Television Arts and Sciences (USA)
Association of America's Public Television Stations, APTS Washington, D.C.
Associazione Italiana Teleradio Indipendenti, ANTI Italy
Australian Film Institute
British Film Institute
Broadcast Education Association (USA)
Cable Television Laboratories
Canadian Radio-television and Telecommunications Commission
Directors Guild of America
Entertainment Services and Technology Association
The European Broadcasting Union
International Television and Video Association
International Television Association
International Webcasting Association
Motion Picture Association of America
North American National Broadcasters Association
National Association of Broadcasters (USA)
Producer Alliance for Cinema and Television (UK)
Public Broadcasting Service (USA)
World Association of Community Radio Broadcasters, AMARC
CinemaSpace contains academic papers, film theory and critique, etc. Page provided by the Film Studies Program at UC Berkeley
Pablov International contains information on Japanese cinema and media culture. Technical stuff on movie industry is available on Cinema Technology Sites. Screenwriters, try this.
American Amateur Press AssociationJournalism & Publishing
American Booksellers Association
American Society of Magazine Editors
American Society of Newspaper Editors
Asian-American Journalists Association
Association for Education In Journalism & Mass Communication
Association of American Publishers
Association of American University Presses
Association of Learned and Professional Society Publishers, ALPSP
Austrian Journalists Club
California Newspaper Publishers Association
California Society of Newspaper Editors
Canadian Association of Journalism
Council of Editors of Learned Journals, CELJ
European Newspaper Publishers Association
International Press Institute
International Publishing Management Association
Journalism Education Association
Magazine Publishers of America
National Association of Broadcasters
National Association of Printers and Lithographers (USA)
National Court Reporters Association (USA)
National Newspaper Association (USA)
National Press Club
National Press Photographers Association (USA)
National Scholastic Press Association
National Society of Newspaper Columnists (USA)
Native American Journalists Association
Newspaper Association of America
Organisation of News Ombudsmen
Poynter Institute (USA)
Printing Industries of America
Society for News Design (USA)
Society of Environmental Journalists (USA)
Society of Professional Journalists (USA)
Swedish Newspaper Publishers' Association
John Makulowich provides a very good source on Journalism, while Journalism and Communications Academic Sites provides links to information on university programs at US, Sweden, New Zealand and Canada. Other sites include European Journalism Links and Newslink