they wouldn't let me add my real zip code! i'm on campus at the University of Georgia, and the campus has it's own zipcode - 30609. they told me it was invalid . so i used 30606 instead, but i'm really 30609, lol.
How to add yourself if you're abroad:
You need to click the "Not in the US" link and start typing the name of your town. If it doesn't show up (and they have tiny hamlets in France, so they should have yours too ), just pick the nearest bigger town and try it again.