Dr. John Penhallurick of Australia manages World Bird Info, a database with taxonomy/nomenclature of all of the known world avifauna in English, French, German, and Spanish. It has excellent search capability. See it here. Look for the tabs at the top to use the search function, or see metadata, other links, and more. One can also link there to Peters, Sibley-Monroe, or Gill 2nd Edition Family lists.
For those interested more specifically in North America, see the American Ornithologist's Union Check-List here.