You would need to use the id that you assigned when registering this widget, rather than the name, as well as add the dynamic sidebar code, that I added in the below set.
<?php if (!dynamic_sidebar('id-of-widget-here')) : ?>
<div class="toppagewidget">
<div class="wrap">
<p><?php _e("This is a widgeted area which is called Top Page Widget"); ?></p>
//add the following line and replace the id
<?php dynamic_sidebar('id-of-widget-here-as-well'); ?>
</div><!-- end .wrap -->
</div><!-- end .widget -->
<?php endif; ?>
Lemme know if that ends up working for ya, or if you need more explanation.