Manually including Webform in a single node
A discussion on Drupal has resulted in a patch that allows you to display a webform in a block (and then you can display that block only on your node tpl page).

EDIT: The patch has been included in the latest version of webform.

Additionally, you could try using this PHP code:

&lt;?php
    $node = node_load($nid);
    print node_view($node);
?&gt;