Hello Friends!
If you want to add a new columns with custom meta fields on list page for any post type then you can do it using the wordpress hooks.
Using hooks you have no need to edit in wordpress core file, you can do all by edit in theme function.php file.
add_filter( 'manage_edit-news_columns', 'news_edit_columns_title' );
//Here news is a custom post type , you can update its value according to post type.
/* We are taking zipcode field as custom filed */
function news_edit_columns_title( $columns ) {
$columns = array(
'cb' => '<input type="checkbox" />',
'title' => __( 'Title', 'Theme_Name' ),
'zipcode' => __( 'Zipcodes', 'Theme_Name' ),
'date' => __( 'Date', 'Theme_Name' ),
);
return $columns;
}
/* Set the zipcode field value to that columns */
add_action( 'manage_posts_custom_column', 'add_news_columns_value' );
function add_news_columns_value( $column ) {
$custom_fields = get_post_custom();
switch ( $column ) {
case 'zipcode' :
echo get_post_meta( get_the_ID(), 'custom_zipcode_value_key',true );
//here custom_zipcode_value_key is the meta key for zipcode
break;
}
}

You can visit on wordpress official site for know more about
manage_posts_custom_column &
manage_edit-post_type_columns functions.
http://codex.wordpress.org/Plugin_API/Filter_Reference/manage_edit-post_type_columns
http://codex.wordpress.org/Plugin_API/Action_Reference/manage_posts_custom_column
Hope you all will be enjoy my code!