Catholics from the U.S.: The many different titles for the Mother of God?

I know that Mary has many different titles in the Catholic Church (Our Lady of Lourdes, Our Lady of Fatima, Our Lady of Perpetual Help, etc.) But who determines what is an official title of the Mother of God? For example, how would I go about getting Pope Benedict XVI to confer upon Mary the title Our Lady of Marlboro Country? I mean, it's glorious out here this time of year, absolutely glorious. Seems like a fittin' title for the Great Mother of God.