Spring to mind;
Ben Fogle - queued behind for some time at a very busy Waitrose - Regatta time i think.
Midge Ure - Bought the family farmhouse, therefore neighbours to the family farm for years and years.
Antony Warrel Thomson - used to host a garden party/hog roast in my village every year growing up.
Urs Schwarzenbach - lived in the village growing up.
Tiff Needell - Met at Le Mans 24, was staying in the same area as us one year.
Boris Johnson - handed me my GCSE certificates, he was my local MP at the time and did the rounds doing this in the 90s.
Seen lots which don't count as meeting, at a distance, due to working at a very large stadium venue for a few years covering all of the events there.