Brighton is well catered for, boasting 2 games clubs (that I know of). The botton link here is for Brighton Wargames Club, can't tell you much as I've not been, but have conversed by email with the chap that organises it and he seems like a top bloke.
The top link is for Brighton Warlords; we play CWC in 6mm, all if you love 6mm like I do, you can also find opponents for Warmaster Ancients, and Napoleonics (playing Nap's Legacy). Also a lot of guys play FOW and the full spectrum of GW tedium.
http://s15.invisionfree.com/Brighton_Warlords http://brightonwargamesclub.wordpress.com/