Unfortunately, I don't remember why I didn't make exhibitor events as content types instead of managing them this way. It was originally done for D6 and I've only made the necessary updates for D7

exhibitor_events.module

<?php
/**
 * Exhibitor Events
 *	
 * Manage exhibitor events such as Celebrity Appearances, Give-A-Ways, etc.
**/

/**
 * Implementation of hook_perm()
 */
function exhibitorevents_permission() {
  return array(
	  'add celebrity event' => array(
		  'title' => t('Add Celebrity Event'),
		),
    'add giveaway event' => array(
		  'title' => t('Add Give-A-Way Event'),
		),
		'add press kit' => array(
		  'title' => t('Add Press Kit'),
		),
  );
}

/**
 * Implementation of hook_theme
 */
function exhibitorevents_theme() {
	return array(
		'seminar_table' => array(
			'variables' => array('seminars' => NULL),
			'path' => drupal_get_path('module', 'exhibitorevents'),
    		'template' => 'seminar-table',
		),
		'presskit_table' => array(
			'variables' => array('presskits' => NULL),
			'path' => drupal_get_path('module', 'exhibitorevents'),
    		'template' => 'presskit-table',
		),
		'event_calendar' => array(
			'variables' => array(
			  'calendar' => NULL,
			  'eventTypes' => NULL,
			  'eventDays' => NULL,
			  'importantDates' => NULL,
			),
			'path' => drupal_get_path('module', 'exhibitorevents'),
    		'template' => 'event-calendar',
		),
		'eventcalendar_item_detail' => array(
			'variables' => array('event' => NULL),
			'path' => drupal_get_path('module', 'exhibitorevents'),
    		'template' => 'event-calendar-item-detail',
		),
	);
}

/**
 * Implementation of hook_menu()
 */
function exhibitorevents_menu() {
  $items['add-celebrity-event'] = array(
	  'title' => 'Add Celebrity Appearance',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('celebrity_event_form'),
		'file' => 'exhibitorevents.forms.inc',
		'access arguments' => array('add celebrity event')
	);
	$items['add-giveaway-event'] = array(
	  'title' => 'Add Give-A-Way',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('giveaway_form'),
		'file' => 'exhibitorevents.forms.inc',
		'access arguments' => array('add giveaway event'),
	);
	$items['add-seminar'] = array(
		'title' => 'Add Seminar',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('seminar_form'),
		'file' => 'exhibitorevents.forms.inc',
		'access arguments' => array('administer nodes'), // right now, only admins
	);
	$items['add-other-event'] = array(
		'title' => 'Add Other Event',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('otherevent_form'),
		'file' => 'exhibitorevents.forms.inc',
		'access arguments' => array('administer nodes'), // right now, only admins
	);
	$items['seminar-schedule'] = array(
		'title' => 'Seminar Schedule',
		'page callback' => 'seminar_display_schedule',
		'file' => 'exhibitorevents.seminar.inc',
		'access callback' => TRUE,
	);
	/** 
	 * I don't know if this should be here.
	 * If it becomes a full-fledged event listing,
	 * then it should; however, if it remains simply
	 * a press kit upload then it needs to be moved
	 * from this module
	 */
	$items['upload-press-kit'] = array(
	  'title' => 'Upload Press Kit',
		'page callback' => 'drupal_get_form',
		'page arguments' => array('presskit_form'),
		'file' => 'exhibitorevents.presskit.inc',
		'access arguments' => array('add press kit'),
		'type' => MENU_CALLBACK,
	);
	  $items['delete-press-kit/%'] = array(
			'title' => 'Upload Press Kit',
			'page callback' => 'presskit_delete',
			'page arguments' => array(1),
			'file' => 'exhibitorevents.presskit.inc',			
			'access arguments' => array('add press kit'),
			'type' => MENU_CALLBACK,
		);
	  
		/** Calendar **/
	$items['event-calendar/%/detail'] = array(
		'title' => 'Event Detail',
		'title callback' => 'eventcalendar_detail_title',
		'title arguments' => array(1),
		'file' => 'exhibitorevents.eventcalendar.inc',
		'page callback' => 'eventcalendar_item_detail',
		'page arguments' => array(1),
    	'access callback' => TRUE,
		'type' => MENU_CALLBACK,
	);
	$items['event-calendar'] = array(
		'title' => 'MATS Event Schedule',
		'title arguments' => array(1),
		'file' => 'exhibitorevents.eventcalendar.inc',
		'page callback' => 'eventcalendar_main',
    	'access callback' => TRUE,
		'type' => MENU_CALLBACK,
	);
	$items['online-press-room'] = array(
		'title' => 'Online Press Room',
		'file' => 'exhibitorevents.presskit.inc',
		'page callback' => 'online_press_room',
		'access callback' => TRUE,
		'type' => MENU_CALLBACK
	);
		
	return $items;
}

function exhibitorevents_get_extras($byId = array()) {
	module_load_include('inc', 'exhibitorevents', 'exhibitorevents.presskit');
	if (array_key_exists('exhibitor_id', $byId)) {
	  $return['giveaways'] = exhibitorevents_get_giveaways(NULL, $byId['exhibitor_id']);
		$return['celebrity'] = exhibitorevents_get_celeb_appearances(NULL, $byId['exhibitor_id']);
		$return['presskit'] = presskit_get_kits($byId['exhibitor_id']);
	}
	
	return $return;
}

function exhibitorevents_get_event($eventId) {
	$type = db_query("SELECT type FROM exhibitorevents WHERE eeid = :eventId", array(':eventId' => $eventId))->fetchField();
	switch ($type) {
		case 'Give-A-Way':
			return current(exhibitorevents_get_giveaways($eventId));
		break;
		case 'Celebrity Appearance':
			return current(exhibitorevents_get_celeb_appearances($eventId));
		break;
	}
	return FALSE;
}

/**
 * @return
 * if both parameters are NULL, return all active give-a-ways
 */
function exhibitorevents_get_giveaways($giveaway_id = NULL, $exhibitor_id = NULL, $date = NULL) {
	$select = db_select('exhibitorevents', 'ee');	
  	$select->join('exhibitorevents_giveaway', 'eg', 'ee.eeid = eg.eeid');
	$select->condition('ee.status', 1, '=');
	$select->condition('ee.type', 'Give-A-Way', '=');
	$select->fields('ee');
	$select->fields('eg');
	if (
		!(is_null($giveaway_id)) &&
		!(is_null($exhibitor_id)) 
		) 
	{
		watchdog('Exhibitor Events', __FUNCTION__ . ' was called with two non-null parameters.  This is not allowed');
		return FALSE;
	}
	
	if (!(is_null($giveaway_id))) {
		$select->condition('eg.id', $giveaway_id, '=');
	}
	
	if (!(is_null($exhibitor_id))) {
		$select->condition('ee.exhibitor_id', $exhibitor_id, '=');
	}

	$results = $select->execute();
	
	$return = array();
	foreach ($results as $result) {
		$result->times = exhibitorevents_get_event_times($result->eeid, $date);
		if (empty($result->times) && !is_null($date)) {
			// a specific date was requested 
			// and nothing is available
			// skip
		} else {
	  		$return[] = $result;
	  	}
	}
	return $return;
}

function exhibitorevents_get_celeb_appearances($appearance_id = NULL, $exhibitor_id = NULL, $date = NULL) {
	
	$select = db_select('exhibitorevents', 'ee');
	$select->condition('ee.status', 1, '=');
	$select->condition('ee.type', 'Celebrity Appearance', '=');
	$select->fields('ee');
	if (
		!(is_null($appearance_id)) &&
		!(is_null($exhibitor_id))
		) 
	{
		watchdog('Exhibitor Events', __FUNCTION__ . ' was called with two non-null parameters.  This is not allowed');
		return FALSE;
	}
	
	if (!(is_null($appearance_id))) {
		$select->condition('ee.eeid', $appearance_id, '=');
	}
	
	if (!(is_null($exhibitor_id))) {
		$select->condition('ee.exhibitor_id', $exhibitor_id, '=');
	}
	
	$results = $select->execute();
	
	$return = array();
	foreach ($results as $result) {
		$result->times = exhibitorevents_get_event_times($result->eeid, $date);
	  	if (empty($result->times) && !is_null($date)) {
			// a specific date was requested 
			// and nothing is available
			// skip
		} else {
	  		$return[] = $result;
	  	}
	}
	
	return $return;
}

function exhibitorevents_get_event_times($eeid, $date = NULL) {
	$select = db_select('exhibitorevents_times', 'et')
		->fields('et', array('date', 'start_time', 'end_time'))
		->condition('eeid', $eeid, '=');
	if (!is_null($date)) {
		$select->condition('date', $date, '=');
	}
	$results = $select->execute();
	$return = array();
	foreach ($results as $entry) {
		$return[] = $entry;
	}
	return $return;
}