Empire of Liberty is a set of free wargames rules for playing the American Revolution. They fit on just two pages.
Direct PDF Download of Empire of Liberty. Author’s Page (I gave the direct download because the page is caught up in one of those infernal webring loops.)
The War Times Journal has a set of free Pre-Dreadnought Naval Warfare rules, designed for 1/3000 scale miniatures.
Small World Productions has a photo tutorial on making hedgerows and field dividers.
Here’s a tutorial on painting the Perry AWI Continentals.
Bloodybacks is a set of free wargames rules for the American War of Independence by Stephen Jones.
Direct PDF Download of Bloodybacks American War of Independence Rules.