Admin Landing Page - How to create?
The reliable way to add and see menu options on admin pages is through [PHP] code, using hook_menu(). Be sure each URL is prefixed with admin/... (for example, admin/sub-section/page-1, admin/sub-section/page-2).

Here's a quick snippet paraphrased from the hook_menu() Drupal API docs:

  function mymodule_menu() {
    $items['admin/sub-section/page-1'] = array(
      'page callback' =&gt; 'mymodule_page1_view',
    );
    return $items;
  }

  function mymodule_page1_view() {
    // ...
  }


I haven't tried tricking the admin screen by adding custom links with "admin/*" at the front, which may or may not work - but the code option will definitely work, I've used that hook more than a thousand times.