London clubs
The mighty South London Warlords (they run Salute each year)
The slightly less mighty South East London Wargames Group (they run the Selwg show in Crystal palace)
BattleUx
Tanelorn
Central London Wargames Club (the only free club in London I believe)
The London Warhammer Gaming Guild
Watford Wargamers
DarkSphere shop(s)
Bad Moon cafe
The Heston And Ealing Wargamers
Orcs Nest has a list of local clubs as well.
https://www.orcsnest.com/clubs.htm
Some are out of date though.
Basically you have a lot of choice.