Implementing alphabetical search in Magento

Create below mentioned files in the app/core/code/local directory with complete directory structure as in Magento core.

app\code\local\Mage\Catalog\Block\Product\List\Toolbar.php
In this file replace the setCollection function with following:

public function setCollection($collection)
    {
        $this->_collection = $collection;

        $this->_collection->setCurPage($this->getCurrentPage());

        // we need to set pagination only if passed value integer and more that 0
        $limit = (int)$this->getLimit();
  $postData = '';
        if ($limit) {
            $this->_collection->setPageSize($limit);
        }
        if ($this->getCurrentOrder()) 
  {
   /**********Alphabetic search Code Start From here**********/
   $postData = Mage::app()->getRequest()->getParam('alpha').'%';
   if(isset($postData['alpha']) && $postData['alpha']!= '' && trim($postData) !='ALL')
   {
    $this->_collection->setOrder($this->getCurrentOrder(), $this->getCurrentDirection())->addAttributeToFilter(array(
                    array('attribute'=>'name', 'like'=>$postData)
                ));
   }
   else
   {
      $this->_collection->setOrder($this->getCurrentOrder(), $this->getCurrentDirection());
   }
   /**********Alphabetic search Code ends here**********/
        }
        return $this;
    }

app\design\frontend\default\default\template\catalog\product\list\toolbar_bottom.phtml

Open this file an replace the code with given below:

<?php 
$search_array = array('A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','ALL');

/*Find if the URL already contains any querystring variable or not */
if (strstr( $this->helper('core/url')->getCurrentUrl(), "&" ))
{
 $separator = '&'; 
}
else
{
    $separator = '?';
}
?>
    <div>
        <p class="view-mode-list-bot">
            <?php 
   $postData = Mage::app()->getRequest()->getParam('alpha');
   foreach ($search_array  as $search_array_value):
   
   /*Clean the URL*/
   if (strstr( $this->helper('core/url')->getCurrentUrl(), "?" ) )
   {
    $new_Url =  $this->str_replace_once('&','?',str_replace("?alpha=".trim($postData['alpha']),'',str_replace($separator."alpha=".trim($postData['alpha']),'',$this->helper('core/url')->getCurrentUrl())));
   }
   else
   {
    $new_Url = str_replace("?alpha=".trim($postData['alpha']),'',str_replace($separator."alpha=".trim($postData['alpha']),'',$this->helper('core/url')->getCurrentUrl()));
   }

   $alphaURL = $new_Url.$separator.'alpha='.$search_array_value;
?>
                
                    <a href="<?php echo $alphaURL; ?>" title="<?php echo $_label ?>" class="<?php echo strtolower($_code); ?> <?php if($search_array_value == $postData){ echo 'remove_under'; } ?>"><?php echo $search_array_value; ?></a>   
                
            <?php endforeach; ?>
           
        </p>
       
    </div>