Just call them back and tell them to place you on their do not call list. they were calling me five to ten times a day trying to refinance my house. I called, asked them to place me on the list, and haven't heard back from them. make a note of the date and time the call was placed, and try to do it from a cell phone so you can document it. If you continue to receive calls, submit your documentation to www.donotcall.gov
You should also sign up for the list if you haven't already. The government does enforces it, and it will prevent a lot of future telemarketing calls.