If I'm reading this right, then I just got really lucky. A week or 2 ago, I remember reading a thread about how rare the codes are, yet at both of the GameStops I visited today, every one of the FF13 boxes I opened, I saw the registration code in each and every one. I bought one along with an 80GB PS3.
DemonAdrastos of Titan(Retired)
PLD83, THF79, NIN85, WAR45, RDM45, SMN31, DRK37, DRG25
Windurst 10, Promathia COMPLETE, Zilart COMPLETE, ToAU 20
Paladin ~ Deimos Adrastos of Behemoth