Hei Tom
camping is allowed on site but you'd probably be better using the onsite accomodation, rooms were about £22 a night last time & are only about 150m from the track & pitting hall! they are single rooms with their own toilet & shower
Ronnys been over 4 times & he takes a cheap flight from Torp to Stanstead then drives up in a hire car. if there are a few of you coming over car sharing would make this quite a bit cheaper
unfortunately its about 160 miles & 3 hours drive!
but with a few of you everyone enjoys a road trip lol
Ronny should be able to help you with some questions but anything else just ask mate