Just became aware of the website lostfilms.eu, an international listing of lost films. It takes a bit to navigate, but it has some good info. If you click on the front page link "3500 entries," you can then scroll to the countries area, for example, and click on the United States to see a listing of 749 US films known to be lost. Unfortunately film titles that begin with "articles" (A, The) are listed alphabetically this way. Left, Emil Jannings in The Patriot.
For the status of silent films I would still recommend silentera.com (and, in fact lostfilms.eu cites them throughout).