Under ICAO, the flight information service (called basic service in the UK, e.g. London Info) is supposed to be able to give you that sort of info.
There are indeed phone numbers for a lot of them but they can be hard to dig out, and obviously, short of having a satellite phone, you cannot really use them while airborne.
The above general comments apply UK and abroad.
A foreign pilot flying via the UK is unlikely to know about Plymouth Military for example.