As others have said, if the Wal-Mart is open 24 hours, they will have it. I've gotten several random non-midnight-release games at Wal-Mart, and even if they don't have Skyrim set out by midnight, just go and talk to the person in the game department and they'll be able to run back and grab you a copy.
Hope your Wal-Mart is open 24 hours

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