Shipping amount field in SQL table.

Good Morning To All, I have a customer who is having one of their internal programmers write an interface that will update GL accounts according to their finance department's needs. They are very specific. One of the things they need is the shipping amounts at a transaction level. I cannot find these amounts anywhere. I read somewhere else that in order for this amounts to be populated the ship to and the shipping carrier had to be filled in on the transaction. I tested it, and I still can't see the totals for the shipping charges. Does anyone know anything about this? THANKS!