Several websites offer information about noted UU historical personalities. One of the most comprehensive is the Dictionary of Unitarian and Universalist Biography developed by the Unitarian Universalist Historical Society.
The Unitarian Universalist Women's Heritage Society has many documents online.
The online Harvard Square Library provides rich UU historical resources, including dozens of biographies of notable American Unitarians and Universalists and a "This Day in Unitarian Universalist History" home page feature.
The UUA website provides a summary of Unitarian Universalist history.