According to their 'About' page, The United States Conference of Catholic Bishops (USCCB) is "an assembly of the hierarchy of the United States and the U.S. Virgin Islands who jointly exercise certain pastoral functions on behalf of the Christian faithful of the United States" whose purpose is to "promote the greater good which the Church offers humankind."
The Official Archive for the Vatican; it is here that you will find the most up-to-date resources straight from Vatican City.