public static class UIElementExtensions
{
    public static void HandleAllPreviewMouse(this UIElement uiElement, RoutedEventHandler handler)
    {
        var elementType = uiElement.GetType();

        foreach (var eventInfo in elementType.GetEvents().Where(ei => ei.Name.Contains("PreviewMouse")))
        {
            var specificHandler = Delegate.CreateDelegate(eventInfo.EventHandlerType, handler.Method);
            eventInfo.AddEventHandler(uiElement, specificHandler);
        }
    }
}

public MainWindow()
{
    InitializeComponent();

    var handler = new RoutedEventHandler(delegate(object sender, RoutedEventArgs e)
    {
        Console.WriteLine("Preview event fired");

        // Uncomment if you want to block event propagation
        //e.Handled = true;
    });

    this.LayoutRoot.HandleAllPreviewMouse(handler);
}

<Grid PreviewMouseLeftButtonDown="Handler">
   <Button/>
   <TextBox/>
   <TextBlock/>
   <AnotherControl/>
</Grid>

private void HookPreviewMouseEvents(MouseButtonEventHandler handler)
    {
        PreviewMouseDown += handler;
        PreviewMouseLeftButtonUp += handler;
        PreviewMouseUp += handler;
    }