Eutychus , that was a useful link, thanks.
The discussion between tower and emergency services was informative, particularly around the conveyance and determination of co-ordinates in order to identify a ground location.
In the interests of education I brought up Google Earth (given it's likely a tool that is available to most people) and attempted to follow the conversation in order to see how easily I could find the location as if I were at the emergency services end.
I - emphatically - make no negative comment, but from what I heard, and in trying to put myself in the seat, it appeared to me that it would be very useful to have a common co-ordinate system available to both ATC and emergency services, and for those operating each end to have training in that. A QRH for such events would seem to be very useful, even if it did nothing more than state what the co-ordinate format is (and, if necessary, how to convert/input that into a common system).
While this is without a doubt a particularly unusual and sad event, I'd expect such information to be very useful for a range of future possible events - and that it's the sort of communication that may need to go both ways (ie. emergency services communicating co-ordinates to ATC and/or operating aircraft).
FP.