or.........call the universities in the area, ask for the music department number, call it, ask the secretary for the name and number of the person in the piano dept you should speak with, then ask that person about their faculty and any other references they could give you.
Besides MTNA, be sure to find out what regional and local groups are active in the St. Louis area. (Some areas have more activity in the local groups than in the national ones.)
With the names you've gathered, now call. And be sure to ask each one for any other references they can give you.
St Louis can be quite a friendly musical area, but like everyplace else, you have to find the niche you want.