As a casual player i havent really noticed amphiteaters/ring of blood was a thing until now
Can someone more knowledgable help me to which ones are out there -
I got Grubushi Arena - Eastern Kingdoms
Ring of Blood - Burning crusade
Amphiteater - Zul Drak (wotlk)
Ring of blood - Wod
Teater in magic land (ashen someting) - Shadowlands
Do you mean open world PvP arenas? The only ones are Gurubashi Arena (which might not even flag you), and the deserted Ring of Blood in Outland. The other arenas you lists are purely for PvE quests.
The closest thing to such arena in Kalimdor is Dire Maul, for not to forget about the arena in Orgrimmar.
Gurubashi - STV (PvP)
Dire Maul - Feralas (PvP)
Ring of Blood - Nagrand (Outland)
Amphitheater - Zul’Drak
Battle of Valhalas - Icecrown
Cruicible of Carnage - Twilight Highlands
Ring of Trials - Nagrand (WoD)
Theater of Pain - Maldraxxus
Might have missed some but these are the ones I can think of.