I finally managed to figure out how to sign in to the chinese website AFTER having bought the CD and card.
I go down all the right paths and input the card number...
I SEE the cd key.. then 5 seconds later, something clicks and the site is gone!
I cant do "back" since I'm using the blizz-launcher explorer and now I cant get my cd key :S /cry

Does anyone have any idea what I can do?
I already tried dialing some numbers in shanghai (I'm in beijing) but no one answered.

[...] *content removed by author* [...]
apologies for original post. i sound harsh when replying from within my mobilephone while waiting for a delayed flight.

The website is:
https://passport.the9.com/passport/index.php
if you want to go there in a normal browser.