Give this a try:
<div id="footer">
<div id="left_footer">
some content
</div>
<ul>
<li><a href="http://www.katiesamsonlaxfest.com/index.html">Home</a></li>
<li><a href="">The Event</a></li>
<li><a href="http://www.katiesamsonlaxfest.com/design.html"> The Cause </a></li>
<li><a href=""> The Teams </a></li>
<li><a href=""> To Donate </a></li>
<li><a href=""> The Sponsors </a></li>
</ul>
<p> Copyright 2010, The Katie Samson Foundation</p>
</div>
I positioned the footer relatively, and then set the newly added div, left_footer, to be absolutely positioned with left 0px and top slightly down.
#footer
{
position: relative;
}
#left_footer
{
position: absolute;
left: 0px;
top: 28px;
}
It appears correctly in Firefox and IE8.