Telefonica, Spain - Deducting money but no service provided

I applied for Telefonica internet services in July 2007. They arranged for a technician to install the service but the technicain never arrived. Since October 2007 I have been attempting to cancel the service that has never been provided and for all monies to be reimbursed to me. As at today's date (28th April 2008) I am still in the same situation with them still deducting money from my account and no service provided. I have tried several routes to resolve this, but all with no success.