I know the thread isn't about the BoB, but a book anyone interested in it should read is "The Battle of Britain" by Richard Overy, a Professor in History at the University of Exeter. I can lend it via email to anyone that requests it, it's fairly short, but gives some well researched information.
Example, on Sept 1, the Germans only had 533 serviceable fighters available. On Oct 1, this number had dropped to 275. Near the end of the battle, England had a slight edge in numbers even. Overy dispels a lot of the notions that it was "just a few" versus many during the battle, while not taking anything away from the RAF. This book changed a lot of the opinions and ideas I had held as sacrosanct regarding the BoB.
Also, some quick numbers regarding Barbarossa:
German Line of Battle:
830 Single Engine Ftrs
90 Twin Engine Ftrs
310 Stukas
775 Long Range Bombers
710 ish recon A/C
First day casualties for the VVS : 1811 aircraft lost, all but 322 on the ground. Luftwaffe casualties 32 planes.
The nest four days score for the L/w : 800, 577, 351, 300 respectively.
By October 5th, over 5,000 VVS aircraft destroyed. FIVE THOUSAND.
edit: After just reading Karaya's post regarding recon, I think that THIS particular point is extremely important. Look at the numbers of recon a/c the Luftwaffe had deployed, nearly as many as they had fighters or bombers. This is a critical point, and like any type of combat, information derived from solid reconnaissance proved to be the deciding factor, at least in my opinion. The first attacks of the operation were by three crack L/W bomber units, one of He11, one of JU88 and one of DO's. They had long lines of VVS aircraft parked to target, the cream of the Russian Airforce, and these 40 or so bombers killed hundreds of aircraft on the ground at critical defense points in the opening minutes of Barbarossa. Their success just mushroomed with other units that came after them.
I think that the effects of the purges cannot be overstated after seeing these numbers, which come from Walter J. Boyne's book "Clash of Wings", another excellent book that encompasses the entire air war of WW2.
Scary numbers to consider. If Russia was planning an invasion, it sure got caught flatfooted on the defensive end of things with the VVS, considering the whooping they took from the incredibly outnumbered L/W in 1941 and early 1942.