This is from another thread
Buddy, here are step by step insructions on how to change your itunes store account country:
Before you change the country, please note:
1) If you have store credit, you must use the credit before you can change countries.
2) You will need to download all purchased content. In addition, rented items must be past their 30-day expiration. For more information on rentals, please see:
3) You must provide a payment method, such as a credit or debit card associated with a valid billing address in the new country. An iTunes Store Gift Card issued in the new country is also an acceptable payment method.
4) Content purchased from the iTunes Store is country-specific. If you wish to upgrade any of your iTunes Store content to iTunes Plus, you'll need to do this before you change countries. The content you purchased while your account was set to the previous country will not be eligible for upgrade once you've changed countries.
5) After you change countries, you will no longer receive application update notifications in iTunes for the apps you purchased in your original country. However, you'll still receive update notifications on your iOS device for any applications installed on it.
6) If you have an iTunes Match subscription, you can't change countries until the subscription has expired.
7) If you have purchased a Season Pass, you cannot change the country associated with your account until that season is done airing and the last episode of the season has been added to the iTunes Store.
8) If you have been using iTunes in the Cloud to download past purchases from your Purchased page, these purchases will no longer appear when you change the country.
To change the country for your account, follow these steps:
1) First, make sure you're using the latest version of iTunes. It's available free of charge:
2) Next, click the following link to open iTunes and access the Apple Account Information page:
3) Enter your iTunes Store account name and password, then click Account Info.
4) On the Apple Account Information page, click Change Country or Region.
5) Enter the updated information and save your changes.
Hope this helps! =D