They are calling here every day. I am also on the don't call list since Sept 2003 (just renewed, good to 2012). I called the 888 number back to try to get some information and it is always a young female. Apparently they have a boiler room operation and use several employees to answer. If I tell them to take me off their list, I get hung up on, promptly. If I try to get information, I can also get hung up on, but some will talk to you a little. The last two said that this is a franchise and that they have several locations, one in Los Angeles area. One just gave me a "Los Angeles" number, 888-279-9099
May I suggest taking a radical move, say a threat to them that would basically force them to reveal themselves to the authorities if they were to file. I know it's risky but it would expose them.
I got a call from 213-221-1021, it was a recording. I found this site and I called some of the 888 numbers that Steve posted. I used the *67 on my phone so that they would not know who it was that was calling them. I kept asking them where they were located. Using up their 888 time on the phone costs them $$$$. I also reported them on the D0 NOT CALL website.