Hey
I'm also Norfolk based, Gorleston, where are you?
Essentially you have about 5 sites, Battlestations at snetterton race track, CQB orientated, great place, my local, love it. Combat action games, in taverham, big open woodland, great place and the guys who run it have a shop near the airport so can help you out with most things. Combat Airsoft in thetford, woodland again, I used to play there but haven't in the last 9 months due to bad sportsmanship and marshalling, but I haven't been there in 9 months, so that could of changed, Skirmish, again woodland based just outside of Norwich, never been, heard reports of nice place but unorganised, but that is from what I heard and not my own opinion as I haven't been there. and finally Tuddenham, 2 groups run games tthere, Gunman and team green, half decent site on an old disused RAF base I believe. My experience was with team green and a little unorganised for my liking, wasn't enough done by marshals to combat non-hit takers.
Hope that helps as brief bit of info, any more just ask fella,
David