Yes, they are. I was looking at some a few weeks ago and they are spread across the country. All I did was google them and some links I found while looking at surplus WWII memoribilia. Let me warn you these guys are SERIOUS and the investment in equipment was unreal. They have some very nice restored weapons, artillery and mechanized units. I never realized the level of authenticity they demand.
Although the entire spectrum of the war fascinates me I am particulary interested in German weaponry and tactics and those are the reenactments I focused on.