How on earth do you make more than one? He straight up refused to tell me.

Pay 50 dollars.

I'm on the paid version.

Just do it? It's in the building list. I had five or six in a coop game the other night. They also can put you above population max (140 with houses).

... you click the town centre button in your build menu.

The building might not be unlocked until level 16ish? I think it requires 400 wood 400 stone

You also have to be on Age 3; from what I remember Age 3 is what triggers me being able to have up to four TCs.

If this was a Starcraft 2 thread, this would be so funny ;D

You can build additional town centers once you hit the Silver Age - similar to the original aoe really.