Z,
Do you really want to see the CustomerID on the form? A common approach
to this situation, is to have the Row Source of the CustomerID combobox
to have its Column Count property set to 2 (CustomerID and
CustomerName), and the Column Widths property set to something like 0;4
(replace the 4 with whatever size you need in order to show the customer
names adequately. Then, you will simply be showing the Customer Name in
the CustomerID combobox - the CustomerID will still be the value of the
combobox's data, but it will be hidden, which in most cases is fine
because the ID is not normally "useful" information anyway.
If you really do want to show the ID in the combobox, and have the
CustomerName show separately in a textbox, there are several approaches
discussed in this article...
http://accesstips.datamanagementsolutions.biz/lookup.htm