If you find the VHF/UHF channels used by the MOA Controlling Agency/Range Control, when the aircraft check-in, part of their mission brief with the Controlling Agency is giving them the freq (or occasionally HAVE QUICK net info) for their air/air comms. Some of the MOAs/Ranges are also open to civilian traffic at certain times/altitudes, so at least one of the VHF Controlling Agency freqs should be published.
Once you get decent at understanding your setup's capability in your area, you'll be able to track the aircraft as they work their airfield's tower & departure channels, switch to a TRACON, to ARTCC, to the MOA/Range Control channel, & then mission channel, all while also hearing them on their"discrete" air/air 'interplane' channel. A lot of times, the callsigns will be 'static' ones they use frequently, and are somewhat easy to track to their aircraft type/mission & squadron, though there's never any guarantee that just because the callsign is "VIPER 02," it's an F-16...
Search 30-88MHz in 25kHz steps, FM Mode, 118-144MHz/148-151MHz in 25kHz steps, AM mode, and 225-400MHz in 25kHz steps, AM Mode.
The more you get into this stuff, the more you'll want to have separate antennas tuned for those spectrums. I'm avoiding some technical quibbling with those freq ranges/modes just to keep things rather simple, and understand there are some abilities for the aircraft to use secure/securish modes (KY-57, HAVE QUICK, LINK-16 & other data-links) & many of the newer production/modification Blocks give the fast-movers SATCOM capability too.