I ordered some products from buyonlinepetshop.co.uk on the 31st October 2008. I understood delivery would take up to 5 days. Three weeks later I never received my ordered goods. I chased them, and another 2 weeks later they told me the products were out of stock. I cancelled the order and asked for a refund. They never respond to my emails, and their phone line just goes to voice mail. Im still waiting for my money. I paid by meastro.

I had that very problem last year. I contacted my Credit Card company, who asked for documentation, so I sent them copies of all the emails and also dates I had tried to phone the company. They eventually credited back the purhase themselves.
So your Maestro issuer - and hopefully they will be able to help. Good luck!