If you are looking for a cheap traditional massage in Korat, one of the cheapest place is near Klang Plaza 2. It is actually in the park in front, where they have sometimes a fair, in the corner. (Google Maps location: 14.972853, 102.098526)
They advertise the foot massage at 120 baht per hour. You often pay double for that service in the city.
This place is maintained by a kind of community (a soldier village in Korat) that started this place. So most of them are wives or relatives of soldier.
It is not the most luxurious place, it is outside without air con but with fan. However, these people are very nice and you might appreciate the price. 🙂