itunes japan store

How do I buy from iTunes Japan?
In the "iTunes Store" at the bottom of the page is a button called "My shop "in which the change in the country of their choice so they could go shopping for the songs there. I have an iTunes account, but it is established in the United States. When I try to buy songs from Japan in the "My Store" will not let me. I know that if I click on Browse> Music> j-pop songs theres bound to be Japanese, but does not have the songs I want. So I'm hoping someone could help me. When I try to configure a new account to the shop from Japan that asks for my credit card, but do not want to use my credit card to use my gift card. please, someone help me?
Well first If you are using an iTunes Music Card reedem before your user account and by right-clicking it says in your mind that should say information then say which country has right now that says change country and then click Change country, but if you have any money that will tell to pass before changing countries. After that you should be able to adapt his country and buy what they were trying to buy.
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