If anyone can contact or knows the contact info of The Mad God?

I'd like to get permission to update his mod Great House Dagoth(Very few things to update to my knowledge, but needed updates.)

So, you want to talk to Sheogorath? You know he's a fictional character, in a video game, made up by Bethesda Game Studios, right?

He is not contactable through these boards, you need to try via PES or one of the modding sites.