you might want to use something like this
addbar.html is page in top frame and changepage.php in bottom frame
addbar.html
<head>
<script>
function openp()
{
var gourl = document.getElementById('url');
bottomframe.location.href = "changepage.php?url=" + gourl;
}
</script>
</head>
<body>
<input type=text name=url>
<input type=button value="Go" onClick="openp();"
</body>
changepage.php
$gourl = $_GET['url'];
include("$gourl");
This is a basic layout you might want to improve this more
Good Luck
TommYNandA