API Functions to Register and Show WordPress List Tables

To add Bulk actions

Bulk action are implemented by overwriting the method get_bulk_actions() and returning an associated array:

function get_bulk_actions() {
  $actions = array(
    'delete'    => 'Delete'
  );
  return $actions;
}

I have write a blog on how to create WP_List_Table.
You can check out ** WP_List_Table – a step by step guide**

You can check this link for more information : http://wpengineer.com/2426/wp_list_table-a-step-by-step-guide/