my mac book is registered to a wrong address

I bought my MacBook refurbished and it is registered to an address in France. This was not an issue until I got an iPhone and it is also by default registered in the wrong country. I am now limited in the apps I can get based in Canada. How do I change the address?

P.S. I am unable to use the apple store because there is 80 cents (in Euros) on it...I can't empty it or add to it..

Please help!