I managed to uncover some more info on Saturday in the Cambridge Public Library, courtesy of the Cambridge Collection.
Knowing the year and parish of death i wondered whether a newspaper would exist, carrying the story. Much to my delight, there was a card index in parish order and so after flicking through to Haddenham 1809, sure enough, there it was.
The Cambridge Chronicle covered the accident in their 22nd July 1809 edition and i was able to see the whole paper on microfiche within moments of finding the card index with thanks to a very helpful lady behind the counter.
The report, part of a list of announcements is short but reveals that poor Philip Newman, a miller, was "caught in the workings of his mill and accidentally killed".
He died on the 20th July, buried on the 21st and the story appeared on the 22nd - a pretty quick succession of events really, i guess!
I visited Haddenham church a couple of weekends ago and didnt find a headstone but estimated where he may have been buried, going by the rest of the stones and their dates.
Ive just moved house and im now just round the corner from the Records Office, so i shall no doubt be returning soon to see what else i can find on this terrible accident.