I just changed this:
<!-- BEGIN SEARCH BUTTON-->
</form>
<form action="http://search.store.yahoo.com/cgi-bin/nsearch" method="get">
<input type="hidden" value="yhst-**my store id**" name="catalog" >
<input size ="0" type="image" src="http://www.marsdust.com/images/powered/php2.gif" value="piano solo" alt="[submit]" name="query" >
<!-- END SEARCH BUTTON-->

to this

<!-- BEGIN SEARCH BUTTON-->
</form>
<form action="http://search.store.yahoo.com/cgi-bin/nsearch" method="get">
<input type="hidden" value="yhst-**my store id**" name="catalog"><input size="0" type="image" src="http://www.marsdust.com/images/powered/php2.gif" value="piano solo" name="query"> <input type="hidden" value="piano solo" name="query"> <!-- END SEARCH BUTTON-->
<br>

There's a bunch of extra junk in there to clean out, but that did the trick.
Jason