Consider boycotting commercial sponsors and let media management know the specific advertisers you plan to boycott. Let the advertisers themselves know, too. Make media and their commercial sponsors sweat. Make 'em realize you want something better. Universities and colleges usually have some form of media education and media literacy programs.
Some schools have courses like The Sociology of Media.
Become a student of media. Intellectually grab the whole phenomenon, shake it up, see what falls out of the pockets. If you re not already involved, get involved in civic activity. Attend candidate forums and town halls. Volunteer for a civic association.