go for it

at the moment, the feeder will accept only csv, designed for google base, advanced features, are deactivated.
Though I think you know enough html, AND the service generates this code for you, here is a full example, of how to integrate the ajax search, into a webpage, barebones example:
HTML Code:
<html>
<head>
<title></title>
<!-- SHOPTACULAR DYNAMIC SEARCH WIDGET 0.2 -->
<script src="http://www.shoptacular.co.uk/beta/res/jquery.js" type="text/javascript"></script>
<script>jQuery.noConflict();</script>
<script src="http://www.shoptacular.co.uk/beta/widget/dynsearch/dynsearch.js" type="text/javascript"></script>
<link href="http://www.shoptacular.co.uk/beta/widget/dynsearch/dynsearch.css" rel="stylesheet" type="text/css" />
<!-- /SHOPTACULAR DYNAMIC SEARCH WIDGET 0.2 -->
</head>
<body>
<div class="ST_Container_AJAX">
<input type="hidden" id="st_id" value="43" />
<input type="hidden" id="st_o" value="price_desc" />
<input type="hidden" id="st_n" value="6" />
<input type="hidden" id="st_limit" value="10" />
<input type="text" value="" id="st_sterm" size="10" name="sterm" /><div id="shoptacular" class="ST_RemoteProductRow_AJAX"></div></div>
</body>
</html>
This one pulls data from the store 'wish-bone', try searching for things like 'pink', 'aerobie' and 'scooter'.