(5) Is the prank caller from a telemarketer? The single most useful tool to stop telemarketers from calling you is placing your number on the Do Not Call Registry. You can place your cell phone and/or landline number on the list through http://www.donotcall.gov (be sure to acknowledge the confirmation email) or call 888-382-1222
and follow their directions.
All persons with a U.S. phone account are allowed to have their phone numbers placed on the Do Not Call Registry. Please allow 31 days from registration confirmation before telemarketers to cease calling. Registry enrollment is valid for 5 years.
(6) Get an "inbound call blocker". This is a screening tool that allows you to select who you receive phone calls from by giving them a special code along with your phone number. There are also numerous similar products that screen and block inbound calls. Check out some products at http://www.commandcommunications.com/index.php and http://www.privacycorps.com/products/.