Ive heard theres a lot of tkd schools around, but haven't come across one anybody know where one is?

Also, anyone know if golden triangle is still running?

There is a school next to Tesco Lotus hang Dong--on the right if you are approaching the building from the main road--go through a little alley way and it's in front of you--not good directions but shouldn't be hard to find.

Central Festival behind the ice skating ring on the 3rd floor.

Assuming two things, that it's for you and your not a kid. But anyway there are many for children all over, mine go to one near a bit North of Central Festival and love it, but I expect they might know. Of course a Thai language might be needed to find out.