Here are some useful links:

http://g2guys.webs.com/ - A men's naturist group based in the West Country.

http://www.gaynaturists.org/ - Gay Naturists International

http://wiki.worldnakedbikeride.org/wiki/London - World Naked Bike Ride

http://www.facebook.com/home.php#!/cardiffwnbr - Cardiff WNBR

http://en.wikipedia.org/wiki/Gay_naturism#Gay_naturism_in_the_United_Kingdom