Learned to fly at Donny, was there the day it closed. Flew one of Doncaster Aeroclub's C152s (what was the other club you mentioned?) to Italy.
Its ex-members/instructors are everywhere: Sandtoft, Gamston, Derby that I know of. One was at Humberside.
If you want to organise a get-together, contact the lady in the Tower at Sandtoft. She probably knows where a lot of them are. Count me in, especially if it's a fly-in get-together! But Xmas Day's out.