Hi there
I am descended from Charles Hiett (depending on how far you have got with your researches, you may recognise my sign-in name...). Although the census says Staunton, this is in fact Stanton Fitzwarren, near Swindon, and when I was over that way a couple of years ago I looked up the parish records in the Swindon Record Office. Charles was born in 1782 and his father was Robert Hiett. The Will of Robert Hiett is available on Documents Online. I have since found out that the Swindon Record Office has a lot of papers from the solicitors who dealt with the estate of Robert Hiett after his death, but I haven't been able to get over there again to look at them - I don't suppose you're anywhere near Swindon?
I am new to this site, so I don't know whether I can send you a private message - if so, I am happy to chat further about my researches into the Hietts so far.