With the help of lurkalot we came up with this,
Place in java script/html block..
<form method="get" action="http://www.google.com/search" target="_blank">
<table style="width: 210px; height: 96px;" border="0" cellpadding="0">
<tbody><tr><td>
<input name="q" size="25" maxlength="255" value="" type="text" />
<p>
<input value="Search" type="submit" /></p></td></tr>
<tr><td style="font-size:75%" align="center">
<input name="sitesearch" value="tinyportal.net" checked="checked" type="checkbox" />
Only search Tinyportal Support site<br />
</td></tr></tbody></table>
</form>
You can change the url and text to your own site