Here is a sample code to get the selected tab by name. I hope this aids you to find ypur solution:
<html>
<head>
<script type="text/javascript"><!-- Don't forget jquery and jquery ui .js files--></script>
<script type="text/javascript">
$(document).ready(function(){
$('#tabs').show();
// shows the index and tab title selected
$('#button-id').button().click(function(){
var selTab = $('#tabs .ui-tabs-selected');
alert('tab-selected: '+selTab.index()+'-'+ selTab.text());
});
});
</script>
</head>
<body>
<div id="tabs">
<ul id="tablist">
<li><a href='forms/form1.html' title="form_1"><span>Form 1</span></a></li>
<li><a href='forms/form2' title="form_2"><span>Form 2</span></a></li>
</ul>
</div>
<button id="button-id">ClickMe</button>
</body>
</html>