how to stop sales calls ?

I have been scheming as to how I can avoid receiving the many unsolicited sales calls at my residence. This is my current plan. I will set up a 900 number at my home. All future requests for my telephone number will be given this new 900 number. I will undoubtedly have to close down my current number and get a new unlisted one for my family to use. This way, if a sales person really wants to call me in the middle of dinner it will be on his dime. I will be happy to say to them..."tell me all about your product, and I mean ALL about it".