I'm no programmer, but here is how I did it... on each of my pages...
Replace the line:
<h1><a href="<SITE_URL>"><SITE_TITLE></a></h1>
with:
<img src="http://YOUR.GRAPHIC.LINK.gif" border="0">
As in....
ORIGINAL
<body>
<div class="container">
<table id="outside" border="0" cellpadding="0" cellspacing="0" align="center">
<tr>
<td>
<table border="0" cellspacing="0" cellpadding="0" width="100%" id="banner">
<tr>
<td width="100%">
<h1><a href="<SITE_URL>"><SITE_TITLE></a></h1>
</td>
UPDATED
<body>
<div class="container">
<table id="outside" border="0" cellpadding="0" cellspacing="0" align="center">
<tr>
<td>
<table border="0" cellspacing="0" cellpadding="0" width="100%" id="banner">
<tr>
<td width="100%">
<img src="http://YOUR.GRAPHIC.LINK.gif" border="0">
</td>