No se si es precisamente lo que buscas:
Código Delphi
[-]
type
TForm1 = class(TForm)
private
procedure WMMove(var Message: TWMMove); message WM_MOVE;
public
end;
...
procedure TForm1.WMMove(var Message: TWMMove);
begin
inherited;
Caption := Format('X: %d, Y: %d', [Message.XPos, Message.YPos]);
end;