cyberdefender made my computer slower than it was, then refused to honor their guarantee! Internet

I saw many TV ads about making computers faster.  The one I saw the most was "MyCleanPC".  I called the number and was somehow talked into three years of service for $199 a year.  I quickly spent almost $600 because they guaranteed that no matter what went wrong with my computer, they would fix it and it would become faster than ever immediatly!  Sounded really good!  After they got into my computer and supposedly cleaned it out and whatever else they did, they called and told me they were finished and I was good to go.  Well, my computer was slower than before, so I called them and they went in again and said  OK, now wer'e finished.  It was no better.  I called the  next day and said I wanted my money back, as there was a 30 day money back guarantee. 

They said they would have a senior technician take care of my problem.  So, they were into my computer for several more hours, making it look like they were doing something.  It didn't get any better.  By this time I was pretty ticked off.  I called again, before my 30 days was up and told them I wasn't satisfied and wanted my money returned.  The agent told me that a financial agent would call me and take care of this.  No one has called me, my 30 days are past and I still have no money.  I took my computer to a local tech.  He said that the cyberdefender was not legitimate and had to clean all of it out of my computer before he could add memory to make it better.  It now runs pretty good for an older PC, but cyberdefender is completely gone from it.  I got ripped off and I fee like a moron for falling for this scam.  I hope i can get my money back.  Anybody that has any suggestions, please help!  Thank you.