Inyour kindle, go to settings and register your kindle with your Amazon ID. If you bought this device from Amazon.com, it would be pre-registered with the buyer's amazon account.
Login to Amazon.com, no matter which country yoAre from. Go to your account and choose the kindle section. Locate your kindle and the you'll find a unique email-id to your kindle account.
You just need to use the email id to send docs to your kindle. It would be auto delivered to your kindle.
Typed from my BB10 mobile. Will add more details soon.