Takhle nějak.
procedure TForm1.Image2MouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
var p: Tpoint;
begin
p:= TImage(Sender).ClientToScreen(X,Y);
Label2.Caption := 'souradnice x: '+inttostr(p.x);
Label3.Caption := 'souradnice y: '+inttostr(p.y);
.
.
.
end;