How can I show data in a form

From: Bongo J (nospam)
Date: 09/17/04 

Date: Fri, 17 Sep 2004 15:31:44 +0100

I am doing an HNC Computing course in the UK and we are using access as a
database. My problem is:
I have three tables Customer, Cost, Bookings.

I have created a query to show relevant info and from the query and tables I
have created a form.

If I want to add to an existing form the join date, which is stored in the
customer table. Do I create a text box and put the entry =[Customer]![Join
Date].

I am doing this in expression builder but all I get showing on the form is
#name?.

TIA
Ali