Today the VSL did a story about the Prelinger Archives which was founded in 1983 by Rick Prelinger in New York City. Prelinger Archives holds approximately 4,000 titles on videotape. Its goal remains to collect, preserve, and facilitate access to films of historic significance that haven't been collected elsewhere.
You can search the site for audio and video and download it for free on their community video page the videos have rights information and when you search you can specify what your needs are. You can search by subject, date collection or creator. You can contribute to the page yourself. There is also a list to links of other digitization projects and issues. According to VSL