<html><head><title></title></head><body>
<script type="text/javascript" language="javascript">
function createlink(id)
{
var div=document.getElementById('infoDIV');
div.innerHTML='<a href=http://site.ru/'+id+'>Go</a>';
div.style.display='block';
}
</script>
<input type="text" id="id" onChange="createlink(document.getElementById('id').value);" >
<div id='infoDIV' style="display:none"></div>
</body></html>