Norton Re-newal

I received a renewal notice on the 12/1/12 for £39.99. I had then been in contact with Norton over a error message, and as a result of delays, the operator extended my subscription by a month. On the 11/2/12 I received a further renewal notice, but this time for £44.99.!!

It seems as if Norton are taking advantage of the situation.

I am not sure how to contact Norton to challenge this situation. Anybody got a link please.

Regards