Helpmedownload.com technical support scam and false marketing Internet

I was browsing the internet looking for firefox download and this company came up and it looked like the official website and asked me to sign up for $15 and because everyone had told me how good it was i thought nothing of it , that was in december 08 and i just checked my bank account on the internet and i found this transaction for $16.40 and knowing that i had not signed any contracts i rang them up and they first told me that i had ticked some box for support at the rate of $15 per month and i know there is no chance that i did . he first said that he could only refund me 1 payment as it was within a 7 day period , then i told him that i was going to seek legal advice he offered me 3 months back and this was the most he was able to refund , then i said that i had seen many other reports about there company on the net and he went away to his supervisor and offered me 6 months but that was the maximum refund he could give , i still argued the point but got no further so i figured that 6 months was better than nothing but that is still 5 months of payments i made for nothing and they get for nothing . does anyone know of a way that i could pursue this any further as they have admitted fault by paying me back the 6 months in a 10 minute phone call ?