Well Mr. Gurudev, That's an interesting thought but I am not quite sure about the viability of that option. See as far as I know, these companies go through yellow pages or white pages and type in some common last names, then start calling random people. Even with my caller id and after several unsuccessful conversations with my phone company they don't seem to be able to trace these calls to a particular number. And my phone company further enlightened me with a piece of information that even if they were able to trace a number it will be from some other countries which are out of US Jurisdictions. I can block all the incoming international calls but as most of the immigrants, I have family members back home and they do call me often. So I can't carry on the option of blocking all incoming international call either. All and all it seems that I am out of options.