One of the more well-known airshow related frequencies that I have documented in my annual airshow guides is 384.550 MHz. Users of this frequency include:
USAF F-15 Flight Demo Team (West), USAF F-16 Flight Demo Team, the USAF Heritage Flight, USAF A-10 Thunderbolt Demonstration Teams, and USAF Combat Search and Rescue (SAR) Demonstrations.
I can now add the USAF F-22 Flight Demo Team (Raptor c/s) to this list. You do not even have to be near an airshow to hear activity on this frequency. These teams also use it for air-air comms as they transit x-country to and from airshows.
Be sure to add 384.550 MHz to your Milcom scanner loadout.