When he registers an account, he will be asked which world he wants. That's when he can choose Little Upsilon. Then he will be assigned a random country.
He has to cancel that country. On the front page of his account there is a box that says "My Countries" and within that box a link says "Add." He has to click on "Add." He will get a link that says "Cancel a Country." He should click on that to get rid of his randomly assigned country.
Now he can go back to the "My Countries" page, click on "Add," choose Little Upsilon, and navigate through the LU map to find an available country near yours.