Once again, tonight, Monday, Sept. 24, 2012, on PBS: American Masters - The Day Carl Sandburg Died. It will be available online after that, but there are numerous text, audio, and video supporting materials (including a trailer) at that link. They don't have a blurb for the biographical film itself, but this is the blurb for the web pages:

It's the life and times of Carl Sandburg on the AM website: Watch the film starting Sept. 24 on PBS; see extended video interviews with the likes of Pete Seeger and the late and great Studs Terkel; hear Sandburg perform and sing in video and audio web features; read curated selections of his writing; plus more–Sandburg's words and world visualized in a series of digital posters, essays, and a photo exploration of the Sandburg archives.

~ Becky in Tucson