Updated 28 August 2015:
New York Public Library: Buttolph Collection of Menus.
Los Angeles Public Library: Menu Collection.
Cornell University Library: Menu Collection.
Cornell University School of Hotel Administration: The Nestlé Library: Menus Collection.
Culinary Institute of America: Conrad N Hilton Library: Menu Collection.
University of Washington: Menus Collection.
Johnson and Wales University: The National Restaurant Association Menu Collection.
Colorado College, Tutt Library: Colorado Menus Collection.
Northwestern University Library: Transportation Library Menu Collection.
Chronology of Inaugural Luncheons.
Seattle Public Library: Seattle Room Menu Collection.
Academia Barilla: Official Dinner Parties of the Savoy Family.
University of Houston: Digital Library: 850s and 1860s Hotel and Restaurant Menus.
The American Menu (blog)
University of Wisconsin-Milwaukee: Prof. Martha Carlin’s list of menus and meal descriptions from ancient times.
University of Nevada, Las Vegas: Menus the Art of Dining.
Naval History and Heritage Command: Menus from Ship to Shore.
University of Hawai’i: Kapi’olani Community College: Rusty Thomas Menu Collection.
Tulane University Digital Library: Louisiana Menu and Restaurant Collection.
National Library of Australia: Ephemera Material: Menus.
South Australia State Library: ‘Sip and Sup’ Menu collection.
Les Menus de l'Histoire, l'Histoire des Menus.