Q: Changing Stores

Try to 'buy' some free app (like Google). When asked for an Apple ID, create a new one. You'll be able to do it without a credit card.

Here's more information: Create an iTunes Store, App Store, or iBooks Store account without a credit card or other payment method - Apple Suppor….

You cannot change to another country store unless you are physically located in the country and have a credit card and billing address in that country. The workaround the other poster gave has to be followed exactly to be able to create an account without the credit card. Also, if you change country stores, you can only change back every 90 days.

Did you 'purchase' a free app while being signed out of the App Store? Or did you just created a new account?