The results are almost always the same. Crime, kids, schools, roads, employment. The media always covers topics like these. The media loves to cover things that get people worked up. Get to know media folks whenever possible.
Radio DJs are especially approachable.
Stop by the studio of your favorite station with a box of donuts and start a friendship. Your favors will be returned on the air. Do that and your message has a good chance of being used. Above all, don't let up. While one media manager may not have the slightest interest in your idea, another will welcome you with open arms.