Lookup for DB Field

Sorry for the newbie question... 

I have several normalized tables like this:

Main Table:
LoadID  CustomerName  ItemNumber
111           Johnson                 123
222           Anderson               321

Item Detail Table:
ItemNumber   Description
123                  45ft Trailer
321                  53ft Trailer


I want to use TDBAdvGrid to display the Main Table, including a column with the Description of the item. How can I achieve this?

Thanks!

Please have a look at the ADOLookup demo in the DBAdvGrid demos folder. This shows such scenario (for the COUNTRY field)