What happened to you is TOTALLY illegal, and your State Attorney General should be notified so they can open an investigation. And, depending on what state you're in... it might be illegal for a "robocaller" or even an autodialer to call your phone (cell or land line) at all. I know it's illegal in my state. Yep, it would be a good thing for you to write to your Atty Gen.
Thanks for your reply - this same thing had occurred to me, but I was using one of those pay-as-you-go phones at the time (where you buy minutes with your bankcard or boost card), so I never had a mailed bill, per se. I called Verizon several times and viewed my phone number's records online, but the "000" number that called never showed up. The $9.99 was just listed as a flat charge. Verizon thought I ordered a ringtone or downloaded something online (my pay-as-you-go plan included data as well), and so there was no way I could prove it without a paper trail. I changed the number finally, and then got rid of the pay-as-you-go plan a couple of months later. I then got a regular plan set up. There haven't been any more calls like that on my new phone, but just to be sure, I blocked all 1-800 numbers to prevent this from happening again. I normally ignore numbers I don't recognize if they call me, but what got me about this one was that I was charged even though it went to voicemail.