If you're interested in officiating, local wrestling referee Mike Junkins provided me with some tips on how to become a ref:
To become a PIAA official, all anyone would need to do is go to the PIAA website (PIAA.org) and register. They would then receive all the documentation and be scheduled for the test. After successful completion of the test, they would be put in touch with the local chapter and begin officiating.
I discovered that many referees choose to officiate to stay in the sport; since coaching can be more time-consuming.