simple javascript help needed!

This script works.  I am using another script (function gup) that sets var range_param as NS's range code that goes in the URL... look here if you're confused and see my script in action: http://www.bestamericanarts.com/Shop/zzzzzzzzzzzzzzzz

<script type="text/javascript">
var range_param = gup( 'range' );
if(range_param == '1%2C1%2C3'){
alert('this is page one');
} else if(range_param == '2%2C2%2C3'){
        alert('this is page two');
} else if(range_param == '3%2C3%2C3'){
        alert('this is page three');
}
</script>

Now I want to change the script a bit to deal with the "search=" value instead of the "range=" value.  I use search results to create dynamic categories by tagging an item with (for example) search keyword "underforty" for all items I have that are under $40.