You can get to most bits on the track but to be honest most of it is pretty boring to take photos from. I'd site yourself on russels personally as you can get pretty close to the track and if you've got say a 200mm Plus lens you can get nice and close. You can see the track here
http://www.motorsportvision.co.uk/sn...snetterton.asp russels looks pretty crap on the map but it's the most exciting bit to watch from with alot of people ploughing straight on etc.
What race series is it? if it's something good i might pop down for a look.