WP Store Locator shortcode

<?php
/*
Plugin Name: WP Store Locator shortcodes
Plugin URI: http://www.damiencarbery.com
Description: Shortcodes for use with WP Store Locator plugin.
Author: Damien Carbery
Version: 0.1

$Id: $
*/

add_shortcode('wpsl_list', 'wpsl_shortcodes');

function wpsl_shortcodes($atts, $content, $code) {
    include_once( ABSPATH . 'wp-admin/includes/plugin.php' );
    if (is_plugin_active( 'wp-store-locator.php' )) {
        return 'WPSL Plugin Not Active';  // Or return nothing.
    }

    global $wpdb;
    $wpdb->wpsl_stores = $wpdb->prefix . 'wpsl_stores';

    $all_stores = $wpdb->get_results( "SELECT * FROM $wpdb->wpsl_stores WHERE `active` ='1' ORDER BY `country`,`store` ASC", ARRAY_A );
    $stores_list = '<table><tr><td>Store Name</td><td>address</td><td>URL</td></tr>';
    foreach ($all_stores as $store_info) {
        $stores_list .= sprintf('<tr><td>%s</td><td>%s</td><td>%s</td></tr>%s', $store_info['store'], $store_info['address'], $store_info['url'], "\n");
    }
    $stores_list .= '</table>';

    return $stores_list;
}
?>