harassing phone calls

I receive about 5 phone calls a day from this company...I have asked them nicely to stop calling, I have been downright rude, I have cussed them out and I have blown a whistle in to the phone on several occasions.  They call from hundreds of phone numbers.  When I block one they call from another.  Nothing seems to work.  I am sick of these calls, I would love to climb through the phone line and choke them to death.  I have reached the point that I want to change my phone number but I hate to because I also run a business out of my home.  It would take a long time to get everyone updated and changed.  What can be done with this company? Someone please help.