if the dns propagation has not been completed that means that the url it self does not really exist, but x10 has set it up so all possible unused domains show the "Domain available" page.
The server that page is on is not the one where your account is, so until the DNS is updated the files does indeed not exist on the server the domain points to.
It can take up to 48 hours before the DNS for new address (new accounts) is updated completely through Internet.