There is a specific address you send them to, with a C/O listed. Unless you send Priority, I doubt, they will get them in time for the Expo. But who knows. You would have to call UD CS and they can tell you exactly where they need to do.
As far as value goes, they look at the value of the player, and the scarcity, to determine which raffle the card goes into. They have different value levels in the raffle. You will never know what you are getting until it shows up.
