“Internet Archive is a non-profit library of millions of free books, movies, software, music, and more.”
I came across this site
while doing a little research on history of some South East Asian countries. They have archived books, for example, about Burma in 1889! Some interesting reading and access to books unobtainable elsewhere. Then I spotted the sections on community audio and video, live music archives and more. Look at som of the old newsreels (from the USA) and war propaganda, old radio and tv shows, and it’s all non-commercial.
A great resource.