Always a good idea in threads like this to plug this book. Out of print, but still available from Amazon:
Postman's theme is the decline of the printed word and the ascendancy of the "tube" with its tendency to present everythingmurder, mayhem, politics, weatheras entertainment. The ultimate effect, as Postman sees it, is the shrivelling of public discourse as TV degrades our conception of what constitutes news, political debate, art, even religious thought. Early chapters trace America's one-time love affair with the printed word, from colonial pamphlets to the publication of the Lincoln-Douglas debates. There's a biting analysis of TV commercials as a form of "instant therapy" based on the assumption that human problems are easily solvable. Postman goes further than other critics in demonstrating that television represents a hostile attack on literate culture.