Law and Contemporary Problems, 66(1,2) (Winter/Spring 2003) is a special issue based on Duke's Nov. 2001 Conference on the Public Domain --- probably one of the few legal conferences with a paper presented by the band Negativland.
Also appearing is Yochai Benkler, NYU prof and author of "Coase's Penguin, or Linux and the Nature of the Firm", an analysis of the economics of open source development that's very cool and also way more precise and thoughtful than Eric Raymond's much-lauded "The Cathedral and the Bazaar".
It also appears that Duke Law has an entire subprogram dedicated to public domain issues. Yay.
UPDATE: Here's a handy link to the archived conference webcast.
UPDATE 2: Most of the above links seem to be broken; see archived papers.