UBU Web is running the 1985 documentary Burroughs: The Movie for free. This should help tide you over until the new Burroughs documentary comes out.
The streaming version is no longer available, but the film makers are remastering the project
You can also check out William S. Burroughs: The Man Within and William S. Burroughs Commisioner of Sewers
(via Dangerous Minds)