I found a great new way to get rid of unsolicited phone calls at work. If they are trying to reach someone else, put them on hold. If they are trying to talk to you, say hold that thought, then put them on hold. At home you can say do the same thing just put the phone down if it doesn’t have a hold button.
Why is this awesome? Time is money to these people. It wastes their time and you don’t have to talk to them. Eventually they’ll hang up and move on to the next person.