I had a similar incident as with Suzanne Report #245575 and #425842
I found a Mac manual online with a good price and purchased through Smartsavingscenter.com & xacti.com. What I did not know is that I also joined a service and they were making deductions to my bank account (which increased with time).
The bank that I was working with called this company for a refund and they only refunded the last months deduction.
I received a cancellation email and also one from the xacti.com POC stating that I had agreed to the membership and they would not return my deductions.