Ong, Walter J. (1982), Orality and literacy : the technologizing of the word , London ; New York : Methuen,

Of course, anything by "Father" Ong is worth reading. You may even find some interviews with him in print.

Chesebro, James W., Bertelsen, Dale A. (1996) Analyzing media : communication technologies as symbolic and cognitive systems, New York : Guilford Press,

This excellent book is the resource for much of this presentation. It also contains the references to Harris, Havelok and Sanders. A must read for a strong theoretical framework.

Goody, Jack. (1996) The logic of writing and the organization of society, Cambridge [Cambridgeshire] ; New York : Cambridge University Press, 1986.