Some 360 games are region locked and others aren't. Also some games released in Asia for example come with full English support so you may find even cheaper prices than you would from the U.S. if you shop around.
For example here's an old link from Cheap Ass Gamer that shows Hitman: Blood Money when it first came out for $40 (it retailed for more than that in the U.S. at the time):
http://www.cheapassgamer.com/archives/hitman-blood-money-360-40-at-playasia.php







