Here you'll find a comprehensive list of early British flying training schools and flying clubs as viewed by their press advertising output. There are some truly classic flying training adverts from the pioneer aircraft manufacturers as well as the schools that trained the RFC & RNAS pilots for WW1 action, a search using the keyword Hendon will prove interesting.
If you're looking for classic RAF or Royal Navy flying recruitment adverts your best bet is to look for Royal Air Force recruitment adverts from 1940-1990. For Hamble graduates (College Of Air Training) try a search using the keyword Hamble. (This link includes some interesting historical adverts from other organisations based at the airfield.)