The following code shows how to change UL list icon.
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css"
href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css">
<script type='text/javascript'
src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/js/bootstrap.min.js"></script>
<style type='text/css'>
ul.nav li a {<!-- ww w .j a v a2 s .c om-->
text-indent: -20px;
padding-left: 35px;
}
</style>
</head>
<body>
<br />
<div class="span4 well">
<ul class="nav nav-list">
<li class="nav-header">Recent news</li>
<li><a href=""><i class="icon icon-play"></i>This is a test.</a></li>
<li class="divider"></li>
<li><a href=""><i class="icon icon-play"></i> Do you shake
your tea?</a></li>
<li class="divider"></li>
<li><a href=""><i class="icon icon-play"></i> New Delta Sky
Club Opens at LaGuardia?s Terminal C</a></li>
<li class="divider"></li>
<li><a href=""><i class="icon icon-play"></i> Love is in the
Air</a></li>
<li class="divider"></li>
</ul>
</div>
</body>
</html>