Google has discontinued this service. A simple replacement can be created.

Add a simple search one site only box to your page with the following code:

<form method="get" action="http://www.google.com/search">
<input type="text" name="q" size="31" maxlength="255" value="" />
<input type="submit" value="Search IT" />
<input type="hidden" name="sitesearch" value="louisville.edu/it" /><br />
</form>

You will need to go to your site settings and remove "form" and "input" from the html filtering and add them as allowed words.

The value set in type=submit line becomes the text on the search button.

The value set in type=hidden line is the address of the site to search.