[edbr]

to use link to the sources in the head

<link rel="stylesheet" type="text/css" href="lightbox/css/jquery.lightbox-0.5.css" media="screen" />
    <script type="text/javascript" src="lightbox/js/jquery.js"></script>
    <script type="text/javascript" src="lightbox/js/jquery.lightbox-0.5.js"></script>

ad a script nominating a div in this case gallery

<script">
        $(function() {
            $('#gallery a').lightBox();
        });
        </script>

then html where ypo want it to appear (in your case sidebar but i have nominated gallery

<div id="gallery">
                  <ul>
                        <li>
                            <a href="photos/image2.jpg" title="Company Snapshot - see your business current situation at a glance "> <img src="photos/thumb_image2.jpg" height="120" alt="Company Snapshot - Quickbooks" /> </a>
                        </li>
                        <li>
                            <a href="photos/image3.jpg" title="Customers and jobs list."> <img src="photos/thumb_image3.jpg" height="120" alt="Customers and jobs list - Quickbooks" /> </a>
                        </li> </ul> </div>

this is a copy paste from a old site bu should be easy to followi think