... detailed list... question about formatting...
Don't format.
I'm in the same situation as you. AVG and Malwarebyes come up clean on my computer and I can't remember the last time either found anything on my computer.
My battle.net account was created when I bought D3 two weeks ago. I have only logged into battle.net and Diablo 3; no other 'Diablo site'.
The software on my computer is licensed and legit. I have not searched for or attempted to use any bot, hack, or gold buying site / program.
I have no idea how my account was compromised but I strongly suspect it wasn't from phishing or malware. I'm now using an Authenticator and will be looking to get items for my now naked barb.
I've tried to have 'reasonable' discussion with others about this issue but all I get in return is, "LOL, ur a dumass!", "stop visiting bad sites!" "you're a liar". Ironically, I'm probably one of the most straight-laced computer users and Diablo gamers in the community. I don't torrent anything. I have no porn on the computer. I only download paid mp3s from Amazon. Still, my account was compromised.