The United States Conference of Catholic Bishop's - The USCCB is an assembly of the Catholic Church hierarchy who work together to unify, coordinate, promote, and carry on Catholic activities in the United States; to organize and conduct religious, charitable, and social welfare work at home and abroad; to aid in education; and to care for immigrants. The bishops themselves constitute the membership of the Conference and are served by a staff of over 350 lay people, priests, deacons, and religious.
EWTN - Ready access to live radio, audio and text libraries, church documents, apologetics, live masses, news, and more.

Catholic Online - A compendium of Catholic beliefs and prayers, with extensive information on angels and saints. Contains a table showing each Pope's name and the year in which their reign ended. Provides links to Catholic periodicals and directories. Beautiful visual art on introductory pages. Uses an external search engine.
The New American Bible - courtesy of the National Conference of Catholic Bishops/United States Catholic Conference. This is the only online version of the official Catholic Bible we have found.