I have collected these references in a Media Anthropology Network discussion:)
The Idea of Public Sphere: A Reader, published by Lexington Books, 2010
*Publics and Counterpublics* – Michael Warner
Radical Media: rebellious communication and social movements, John Downing.
Birgit Meyer and Annelies Moors (2006, Indiana University Press) offer a stimulating and anthropologically driven discussion on public sphere in the introduction of their edited volume Religion, Media, and the Public Sphere.
Jürgen Habermas, “The Public Sphere” in Rethinking Popular Culture
The Television Studies Reader (2004) by Colin Crouch, The Global, the Local and the Public Sphere
The Indian Public Sphere. Readings in Media History Edited by Arvind Rajagopal 2009,Oxford UP
Calhoun,Craig (Hrsg.): ³Habermas and the public sphere², MIT Press, Cambridge (Mass.), 1992, Ibid.: The Public Sphere in the Field of Power <http://www.ssrc.org/calhoun/wp-content/uploads/2010/09/The-Public-Sphere-SSHRev3.pdf>.² Social Science History vol. 34 (2010) #3: 301-36
ibid: ³Imagining Solidarity: Cosmopolitanism, Constitutional Patriotism and the Public Sphere. <http://preview.ssrc.org:8080/staff/calhoun/publications/ImaginingSolidarity.pdf> Public Culture 14(1): 147-72.
Eickelman, Dale F. (Hg.) 1999: ³New Media in the Muslim World. The emerging Public Sphere², Indiana UP, Bloomington, 213 S.