I did the sound effects and sound reinforcement for “Oklahoma!” for the Amherst PTA play in 2012. The musical has very few sound effects, just door knocks and gun shots, so this page just includes the microphone notes.
After several years of allocating microphones by hand, I wrote a compiler for them. It reads a description of who plays each character, and when each character enters and exits the stage. I used it for this production of “Oklahoma!”. You can find this compiler on github, at this URL: allocate_microphones.