All these videos were made by talented independent film and videomakers, and these people retain the copyright to their work. They are not public domain.
You need to license this footage for any use, just like you would anywhere else. We only have permission to license some of the footage in our archive; hopefully we can give you a lead on how to find the rights holder if we can’t license it ourselves. Because the work in the archive was made by so many different people, rates and permissions are going to vary based on which pieces you pick. If you are interested in purchasing stock footage, please email us and we’ll talk. We’re reasonable about working with independents on limited budgets. We can also help you find additional footage that hasn’t been digitized yet.