Have you ever gotten a call from a telemarketer that starts off with a recording? Usually it's "Anne with account services" with some sort of offer to lower your interest rate. Other times, it's a recording from someone else offering cheap medical insurance or a Discover Account Services (not to be confused with Discover Card) or some other service that sounds a lot like a scam. Whatever the voice on the recording is offering, you're met with two choices: Dial 1 to speak with a rep or 4 to be added to their "do not call" list. Of course, all dialing 4 does is disconnect you and the calls keep coming. And, if you call the number back, you just get a generic "out of service" message.
Most of these calls are coming from call center boiler rooms with VOIP phones. Some of them are even using Magic Jack devices. Thankfully, there's still something you can do if these calls are driving you crazy. All you need to do is look up the phone services provider of that number via telcodata.us. On the left-hand navbar of the site, you'll see a heading that says "Area Code/Exchange Listings By". Click the "Area Code/Exchange" link under it. Then, enter in the three digit area code and the three digit exchange and search for the provider. Once you have the provider's name, do a Google search for their contact information and call them.
Remember, the telephone services provider is probably a legitimate business and simply provides telephone services to the boiler room telemarketers. So, make sure you're polite when you contact them. Kindness will go a long way here. Simply tell them that you'd like to lodge a complaint about abuse coming from a number they own. They'll take down the number that was calling you along with the number that the scammers have been calling and, if everything works out, they'll make sure that you're never called again.
Your mileage may vary depending on a lot of factors, but, for me, I can say that I haven't been contacted by Anne from account services in two weeks whereas I used to get a call twice a day. And don't bother trying to get a contact information connected to the number that has been harassing you. Most providers strictly protect their customer information, so, unless you have a subpoena, you won't be able to contact Anne from Account Services directly.