If you have an answering machine, you can outfox these predators. Record Special Information Tones (see the attached url to hear them) at the beginning of your outgoing message. This tells anyone using an autodialer that the number is out of service. A real person won't care, but then they have to listen to you tell them off. I've used these tones for the past few years and the number of telemarketing calls has dropped. I sincerely hope it helps other people to avoid these pests.

http://www.yourhomenow.com/sit.html