Can't get my head around this one:

How do you have a select menu automatically generated from another table? I'm trying to associate several contacts (lawyers, realtors, processors, etc.) with each record in a table of real estate deals. I'm keeping the contacts in a separate contacts table, but I want users to be able to choose each of these contacts from several select menus (or, more likely, multiple-select menus) when they add a new record to the first table.

I'm new to SQL, so pardon me if this is a newbie question.