Demo for http://theeventscalendar.com/support/forums/topic/add-text-to-community-event-submission-form/

functions.php

<?php
// https://gist.github.com/cliffordp/6ed4de93895fe2acd959
// demo for http://theeventscalendar.com/support/forums/topic/add-text-to-community-event-submission-form/

add_action( 'tribe_events_community_before_the_event_title', 'forum_1022861_add_review_notice_to_comm_ev_form' );

function forum_1022861_add_review_notice_to_comm_ev_form() {
  $output = '<div style="margin-bottom: 12.75px;" class="tribe-events-community-details eventForm bubble">
  <div class="tribe_sectionheader">
    <h4>Notice:</h4>
  </div>
  <p>The form will be sent in as draft and has to be approved before it is visible in the events calendar.</p>
  <p>We usually review submissions within 4 business hours.</p>
  </div>';
  echo $output;
}