Нужна помощь в присоединении к столу

Стандартный SQL-запрос для этого (при условии, что вам нужны и идентификатор, и название места проведения):

SELECT a.lname as lname, a.fname as fname, a.email as email,
    a.address1 as address1, a.address2 as address2, a.city as city, 
    a.state as state, a.zip as zip, a.venue_id as venue_id,
    b.venue_name as venue_name, a.dtelephone as dtelephone,
    a.etelephone as etelephone, a.tshirt as tshirt
FROM volunteers_2009 a, venues b
WHERE a.venue_id = b.id
AND a.venue_id IS NOT NULL
UNION ALL
SELECT a.lname as lname, a.fname as fname, a.email as email,
    a.address1 as address1, a.address2 as address2, a.city as city, 
    a.state as state, a.zip as zip, a.venue_id as venue_id,
    '' as venue_name, a.dtelephone as dtelephone,
    a.etelephone as etelephone, a.tshirt as tshirt
FROM volunteers_2009 a
WHERE a.venue_id IS NULL

SELECT lname, fname, email, address1, address2, city,   
state, zip, b.venue_name, dtelephone, etelephone, tshirt FROM   
volunteers_2009 a, venues b  
where a.venue_id = b. venue_id

используйте правильный псевдоним, если обе таблицы имеют столбцы с одинаковыми именами.

--- ИЗМЕНИТЬ, чтобы все строки из мест проведения использовали внешнее соединение как

SELECT lname, fname, email, address1, address2, city,   
state, zip, b.venue_name, dtelephone, etelephone, tshirt FROM  
volunteers_2009 a(+), venues b  
where a.venue_id = b. venue_id