In your theme directory, open the header.php and look for :
<!-- start navigation -->
<div id="nav">
<ul class="navigation">
<li class="active"><a href="http://wp-answers.com/demosite"><span>Home</span></a></li>
<li><a href="http://wp-answers.com/demosite/?s=open"><span>Open Questions</span></a></li>
<li><a href="http://wp-answers.com/demosite/?s=top"><span>Top Users</span></a></li>
<li><a href="http://wp-answers.com/demosite/?s=popular"><span>Popular</span></a></li>
<li><a href="http://wp-answers.com/demosite/?s=about"><span>About</span></a></li>
<li><a href="http://wp-answers.com/demosite/?s=contact"><span>Contact</span></a></li>
</ul>
</div>
<!-- end navigation -->
You can enter a new link there,
If not comfortable doing this - email me your ftp details and I will do it for you.
Hope that helps.
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