xymox12

add_action('em_template_events_search_form_ddm', 'my_em_styles_search_form');
function my_em_styles_search_form(){
$custom_attrs = get_meta_values('Hosted_by','Event');
?>
  <!-- START Styles Search -->
	<select name="host">
		<option value=''>All Styles</option> 
		<?php foreach($custom_attrs as $meta_name): ?>
		 <option value="<?php echo $meta_name; ?>" <?php echo ($_GET['host'] == $meta_name) ? 'selected="selected"':''; ?>><?php echo $meta_name; ?></option>
		<?php endforeach; ?>

xymox12

<?php
// custom host taxonomy for events
add_action( 'init', 'register_my_taxonomies', 0 );

function register_my_taxonomies() {
$labels = array(
    'name'                          => 'Hosts',
    'singular_name'                 => 'Host',
    'search_items'                  => 'Search hosts',
    'popular_items'                 => 'Popular hosts',