Broadcasting and Cable Magazine , as well as several other broadcast-related publications, regularly carry ads for jobs. You might mention in the cover letter that you will be calling in about a week to see about an interview. That way, they may keep your resume handy so they can refer to it when you call. Finally, learn to handle rejection without dejection. While you are striving to break into this competitive field, you'll be competing with many applicants with similar qualifications.
Many candidates give up hope and drop out along the way.
Module 69 of the Television Production cybertext covers many of these same topics.