Wargames Rules 1685-1845 is a set of classic WRG rules from 1977. I own a copy, but you can get your own in pdf form at the link.
Lilibulero (.zip file direct download) is a set of free wargames rules for wargames in the 1600 to 1700. The author writes:
These rules are shamelessly adapted from the old Wargames Holiday Centre “Marlburian Rules” written by Mike Ingham, with chunks lifted from Barry Hilton’s “Under the Lilly Banners”, produced by the League of Augsburg. Barry’s set was in turn based on Mike Ingham’s original. Another variant of Mike Ingham’s rules is “A Grim Panoply”, written by Phil Olley, and I have to admit I’ve also raided Phil’s rules for ideas. The orders section was adapted from Pete Berry’s English Civil War set “Forlorn Hope”. If imitation is the sincerest form of flattery, then these three guys should be delighted!
Angus Konstam, 2006