Visited 21.2.2009. Approached from Burley Road and then Hollis Place. The stone sits at the junction of Hollis Place and Westfield Road, which continues west past the stone as a footpath. A steep set of steps leads down to the stone from the north.
The stone is sadly unloved and sprayed with grafitti, which I suppose at least means that someone has noticed it. It's not in its original location, and when you read the small information plaque, you also realise it's not actually the original stone itself, but a replica (a cast?). The sign gives no clue as to what happened to the original.
A small note to Paulus' directions - the Oblong Resource Centre has now moved to another part of town (near Hyde Park Corner).