Matakishi has some instructions with photos for making World War II era buildings out of sheets of cork.
From Jim Wallman comes Blitz, one of the more imaginative miniatures rules sets I have encountered. In it, you command squads of firefighters coping with the dangers of the London Blitz of 1940 – 1941.
Micro Armor Devastation is a set of fast play miniatures rules for land and air combat from World War II onward. They’re very nicely done in a pdf format.
Assault Gun is a set of free wargames rules by David Kershaw. David writes:
This rule set is designed to allow players to simulate large actions of the Second World War using miniature models. Each division is represented by less than 10 bases (regiments and battalions), so players can command several divisions each, and play a recognisable action of the Second World War.
JD Burgess’ site has a list of major WWII air war campaigns. For each, he has lists of the planes that participated, with links to photos and information.