Thanks for all the info everyone!
I hadn't even given vertical airspace restrictions a single thought when thinking about Kenley.
It looks, from the BGA site, like my options would include Kent, Booker, and Surrey Hills. Based solely on them being the nearest.
I am surprised by some of the prices quoted though. It certainly isn't cheap! £90 for a 15 minute trial flight at Kent. Even more at Booker.
Weekday flying isn't an issue for me so I think I'll contact Surrey Hills at Kenley and see if it's something I definitely want to spend money on before commiting to the more expensive courses and aerotows.
Now if anyone is planning a sacrifice to the sun god, can you let me know so I can book some flying time!
Thanks