SHokuf:
http://www.zen-cart.com/forum/showthread.php?t=90303&highlight=search+header+image&page=2
I searched high and low to another solution to editing this sidebox code like this, but I could not find another solution anywhere.. So reluctantly, I edited the sidebox. However, I did not like the idea of using a URL for the image location (as is suggested in the link Shokuf posted), and preferred to stick to using a relative link instead. Plus I wanted to maintain consistency by using the same location as other Zen buttons. Hope this is useful to others..
If it helps.. here is the code I used to fix my search sidebox. Copy the tpl_search.php from the default_template to your own template folder as follows: includes/templates/YOUR_TEMPLATE/sideboxes/tpl_search.php. I used this in ZenCart version 1.3.8a, and it worked perfectly! Please see the highlighted section. Change "YOUR_TEMPLATE" to the name of your template folder.
<?php
/**
* Side Box Template
*
* @package templateSystem
* @copyright Copyright 2003-2006 Zen Cart Development Team
* @copyright Portions Copyright 2003 osCommerce
* @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
* @version $Id: tpl_search.php 4142 2006-08-15 04:32:54Z drbyte $
*/
$content = "";
$content .= '<div id="' . str_replace('_', '-', $box_id . 'Content') . '" class="sideBoxContent centeredContent">';
$content .= zen_draw_form('quick_find', zen_href_link(FILENAME_ADVANCED_SEARCH_RESULT, '', 'NONSSL', false), 'get');
$content .= zen_draw_hidden_field('main_page',FILENAME_ADVANCED_SEARCH_RESULT);
$content .= zen_draw_hidden_field('search_in_description', '1') . zen_hide_session_id();
if (strtolower(IMAGE_USE_CSS_BUTTONS) == 'yes') {
$content .= zen_draw_input_field('keyword', '', 'size="18" maxlength="100" style="width: ' . ($column_width-30) . 'px"') . '<br />' . zen_image_submit (BUTTON_IMAGE_SEARCH,HEADER_SEARCH_BUTTON);
$content .= '<br /><a href="' . zen_href_link(FILENAME_ADVANCED_SEARCH) . '">' . BOX_SEARCH_ADVANCED_SEARCH . '</a>';
} else {
$content .= zen_draw_input_field('keyword', '', 'size="18" maxlength="100" style="width: ' . ($column_width-30) . 'px" value="' . HEADER_SEARCH_DEFAULT_TEXT . '" onfocus="if (this.value == \'' . HEADER_SEARCH_DEFAULT_TEXT . '\') this.value = \'\';" onblur="if (this.value == \'\') this.value = \'' . HEADER_SEARCH_DEFAULT_TEXT . '\';"') . '<br />[B]<input type="image" src="includes/templates/YOUR_TEMPLATE/buttons/english/button_search.gif" value="" />[/B]';
$content .= '<br /><a href="' . zen_href_link(FILENAME_ADVANCED_SEARCH) . '">' . BOX_SEARCH_ADVANCED_SEARCH . '</a>';
}
$content .= "</form>";
$content .= '</div>';
?>
