Mates,
I registered and jumped through the hoops to reply. I am making books for pcgen, I too am a big fan. I'm focused on 3.5 edition, but have branched out to support others:
4e - working on getting this working
D&D Next - Play test just for kicks and giggles
Monte Cook's World of Darkness - d20 take on World of Darkness
Blue Rose Campaign Setting (True20)
3.5 is where my main focus is, I have all three core rule books, and several of the Complete Series. I'm finishing up Tome of Battle, and getting a 3.5 version of Oriental Adventures.
If you are interested in helping me out, check out my repo -
https://github.com/BahamutDragon/pcgen or drop me a line.
Best,