I keep a Pro96 with Pro96com going 24/7 on one of the towers I can monitor locally. All the known TGs are color tagged. That makes it simple to look at the channel grants and affiliation logs for new TGs on the system.
I also keep a BCD996T going with local and known TGs locked out so they will pop up. That machine is controlled with ProScan so everything it gets is recorded with time stamps, tower info and TG info.
All it takes is the wherewithall

(Being slightly radio nuts helps too)
Bruce
Bruce