TRY:
<a id="aa" href="http://community.csdn.net/Expert/topic/4420/4420821.xml?temp=.7602808">test</a><script language="javascript">
alert(aa.href);
</script>
<a id="aa" href="http://community.csdn.net/Expert/topic/4420/4420821.xml?temp=.7602808">test</a><script language="javascript">
alert(aa.href);
</script>
alert(aa.href);
</script>
<link href="afsdfs.css" type="text/css">
</head>
<body>
<script>
var v=document.getElementsByTagName('LINK');
alert(v[0].href);
</script>
</body>