Silverstone is awkward though because the greater distances mean yo'ure just very tight on space to get decent shots - it's my local track but there are very few places I've found for getting nice stuff without shooting through a fence, which is pretty much an instant no-no for publication.
Plus, most of the larger events there have terms on the ticket which state that any pictures you take are for your own personal use only and woe betide you if you try and do anything remotely commercial or public with them. It's a while since I've been to a smaller event at Silverstone to know if their terms are the same, but from what I remember FIA GTs and Le Mans series both did this, as did Brands for the truck racing.