Well, I guess I would hold the Men responsible for the Concept of God to be so readily pushed in our culture. I wouldn't Blame the men who first wrote about God, but those who USED what would and should have gone to myth like so many other "supernatural" religions as a means to control and mold mankind's future through fear and ignorance.
To those men I would exact the same vengeance on them they saw fit to do to those whom went against the church's nefarious plot back in the age of darkness.
No punishment for a concept, but punishment for those that pushed the myth and kept it alive through fear and indoctrination.
Then I would sue God's representatives on Earth (by whatever name) to cough up, out of their coffers, to pay for the damage.
Then I'd sit back and start counting to see how long it would take the churches to have their tame politicians change the law so that the insurance companies could once again be held responsible.
Ah, if only... :(
But if I could hold him accountable for anything it would be for creating humans and his punishment would be to live and die as one.