I've never experienced much of a clique on Farnham's waters. (Member of some 20 years). Some of the waters offer a real challenge and so, anglers fishing them might not be willing to spill the beans on the details of years of work without something in return. Other waters are easier.
It might be a bit of a drive from Brighton though. There are quite a few members from Portsmouth who fish FAS waters.
Let me know if you want any specific info on any of the waters (www.farnhamanglingsociety.com)