Here's an excerpt from a recent email to clients:

GETTING SOME "FACE TIME"

Do not call-in sick to get a day off for an interview.

Do not drop by a station unannounced just because you happen to be in town: make an appointment.  If the news director wants to see your reel first and won't give you an appointment, accept it: that is how he/she does business.  If you plan to travel any time soon, let us know your itinerary and we will send some queries in advance to try to generate some interest and possibly an interview for you while you're in the area.  Don't be upset if nothing comes of this.  If there are no openings, you're unlikely to get an interview.  If they're not looking for your type, you're unlikely to get an interview.  Very few News Directors bother to sit and chat with people unless they (a) have an opening, and (b) are looking for your type.