A League of Ordinary Gamers has sets of paper counters for Warmaster armies including: New Kingdom Egyptians, Assyrians, Brettonian, Chaos, Dark Elves, Dwarf, Empire, High Elf, Lizardmen, Orcs, Skaven, Undead, Vampire Counts, and Wood Elves.
Paper counters are a good, quick and reasonably cheap way of trying out a system.
The Wrath of Zombies blog has a set of free RPG rules for Mass Combat. While written for the author’s own Thundarr style game, they are applicable to a wide variety of rules and settings.
The Character For Every Game Blog offers some really neat dungeon geomorph tiles, as well as a few nice complete dungeons. Plenty here to look at.
Creating a fantasy world? Running a medieval fantasy RPG? Here’s a great article on Medieval Demographics, based on the Paris tax lists of 1292 and other original sources.
Strage Grogge is a set of free wargames rules for playing Black Powder fantasy games.