[kh99]

Well, for the form part I think you just need to get rid of the <? and ?>, like

<td><div><form action="$_SERVER['PHP_SELF']">
<p><b><label for="domain">Domain/IP Address:</label></b> <input type="text" name="domain" id="domain" value="$domain"> <input type="submit" value="Lookup"></p>
</form>

I'm also not sure if "$_SERVER['PHP_SELF']" will be what you want there.

Also, the PHP you have there won't work in a template, [S]you'll need to put it in a plugin, which means you'll have to find a hook where it can be executed.[/S] Edit: Sorry, I reread your post - you won't necessarily need a plugin if you've got your own php file.

Both of these come from the fact that a vbulletin template is kind of like a php stand alone program but not quite, you don't need <? and ?> and you're limited to a certain set of functions you can call in conditionals.