How do I find television/radio broadcasts or transcripts?

Meet the Press from Alexander Street Press opens up a wealth of information to libraries by making over 1,500 hours of footagethe full surviving broadcast run to dateavailable online in one cross-searchable interface. Since its television premiere in 1947, Meet the Press has cemented its position as an institution in broadcast journalism. For the first time ever, network televisions longest running programwith its thousands of interviews, panels, and debatesis available via streaming online video. Now, students and scholars have unprecedented access to this treasure trove of material, including many episodes not seen since their original broadcast.
From their website

The complete video archive of the C-SPAN cable network. Congressional debates, hearing, presidential speeches, and more.

The Vanderbilt Television News Archive is the world's most extensive and complete archive of television news. We have been recording, preserving and providing access to television news broadcasts of the national networks since August 5, 1968.

The collection spans the presidential administrations of Lyndon Baines Johnson, Richard Nixon, Gerald Ford, Jimmy Carter, Ronald Reagan, George H.W. Bush, Bill Clinton, George W. Bush and Barack Obama. The core collection includes evening news from ABC, CBS, and NBC (since 1968), an hour per day of CNN (since 1995) and Fox News (since 2004).

Provides access to global news and business information, including local newspapers, same-day newswires, company reports, and media programs. Content is available in many different languages, including Chinese, French, German, Japanese and Russian. Stock data and indices are available for 5 years.

A full-text news and information service that provides access to newspapers, magazines, news wires, news transcripts, business, and legal information. Dates of coverage vary by title.