Get on the "Do Not Call" lists

To reduce the value of your contact information among advertisers, add your name to the 'Do Not Call/Email' lists.  Even though it may take a little while for advertisers to pick up the change, it's a good and easy step.  There may still be hackers or less careful advartisers out there who don't pay attention to 'Do Not Call/Email' lists, but when your name's on a list it's not worth as much on the black market.