Yes as others say, Silverstone is pretty much in the middle of no where as far as tourist attractions (or anything else) are concerned.
I live about 2 hours drive from the circuit, but to save us traveling every day, in 2005 we stayed in a hotel. The closest we could get
was 12 miles from the circuit, it was shabby, expensive and still in the middle of no where. I wont be doing the same again.
If yourself and your wife would like a more stress free, pampered GP experience with plenty to do away from the circuit I'd heartily
recommend the Italian GP at Monza (staying in Milan) or the European GP at Valencia. Neither are expensive, public transport is
excellent and with the cities of Milan and Valencia at your doorstep you wont get bored or hungry!
I always buy my tickets straight from the circuits official website.