A kód, amit a HTML kódnézetbe kell beillesztened (<> gomb !!!):

<FORM name=banesearch onsubmit=banesitesearch(this)
action=http://www.google.co.hu/search method=get>
<P>Keresés az oldalon:<BR><INPUT id=hiddenquery type=hidden name=q> <INPUT
style="WIDTH: 200px" value="na hajrá..." name=qfront> <INPUT type=submit value=Keresés><BR>
<DIV style="FONT: bold 11px Verdana">Google:<INPUT type=radio CHECKED name=se>
Yahoo:<INPUT type=radio name=se> MSN:<INPUT type=radio name=se> </DIV>
<SCRIPT type=text/javascript>

// All-in-one Internal Site Search script- By JavaScriptKit.com (http://www.javascriptkit.com)
// For this and over 400+ free scripts, visit JavaScript Kit- http://www.javascriptkit.com/
// This notice must stay intact for use

//Enter domain of site to search.
var domainroot="www.bane.gportal.hu"

var searchaction=[ //form action for the 3 search engines
"http://www.google.com/search",
"http://search.yahoo.com/search",
"http://search.msn.com/results.aspx"
]

var queryfieldname=["q","p","q"] //name of hidden query form for the 3 search engines

function switchaction(cur, index){
cur.form.action=searchaction[index]
document.getElementById("hiddenquery").name=queryfieldname[index]
}

function banesitesearch(curobj){
for (i=0; i< document.jksearch.se.length; i++){ //loop through radio to see which is checked
if (document.jksearch.se[i].checked==true)
switchaction(document.banesearch.se[i], i)
}
document.getElementById("hiddenquery").value="site:"+domainroot+" "+curobj.qfront.value
}

</SCRIPT>
</FORM>

Megjegyzés:
hát nekem egyáltalán nem működik, de azért ti attól még próbálkozhattok :P

Illusztráció: