Does he really live in a castle?
No, there are some nice houses there though. I don't know his exact address nor would share it on here if I did.
He lives (unless he's moved recently) in a place called Holme in Cambs, which is just off the A1 just a bit south of Peterborough.
It's nice there, there is an airfield behind the village people fly light aircraft from but I believe it was originally built during the second world war used by the RAF. I pub which isn't bad although I've not been there for years.
Because it's in the middle of the fens, it's actually below sea level, there is the "fen post" in some woods about a mile away that is the lowest point in England (I want to say whole of the UK) and the post (which looks like a metal lamp post) was piled into the ground however many years ago and the top was level with the ground, now it sticks up out of the ground like a lamp post, to show you how much the land has all sunk over the years.
I've never met him.