You can’t get the Fantasy Trip any more, but you can get Dark City Games’ Legends of the Ancient World, a free tactical RPG that uses the same mechanics.
Viking Battles In the Anglo Saxon Chronicles
Merlin Larson offers a list of battles with Vikings from the Anglo Saxon Chronicles. The most interesting thing he found was that – contrary to the mythology — the Vikings were not necessarily superior in battle to the Anglo Saxons.
Uniforms of Byzantium Through 1453
The New York Public Library Systems Digital Library has digitized images of thousands of plates, prints and paintings, including these of the uniforms of Byzantium through 1453.
UK Battlefields Trust Resource Site
The UK Battlefields Trust has an extremely interesting site with information, maps, ground and air photos of English battlefields from the Celtic and Roman periods through the Stuart uprisings.
Battle of the Five Armies Scenario
Merlin Larson has a well researched scenario for wargaming the Battle of the Five Armies from The Hobbit.