I think the nearest club to me would be based at Kenley.
Nearest isn't necessarily best just as cheapest isn't necessarily best. use the BGA website, look at the websites of the easy-to-get-to clubs, pay some visits and then decide.
Is gliding a backwards step? No. Instead of being a mode of transport it's a very skilful activity - far more than power flying. We have quite a few CPLs (including two of the best XC pilots) and several PPLs at my club who all find gliding a challenging and enthralling sport. We will also be flying, safely, at my club in winds that will have the local GA strip grounded.