Kanae has put some up on her site.
To input them:
On the main menu, go to 通信モード (Third Option down) → フレンドカード設定 (Third Option down)→ メッセージ編集 (Second Option under Basic Info)
On the input screen, delete anything written with Square Button, and then press Select until it changes the input to the narrower roman letters (second set of roman letters you will see). Input the password of your choice in as your message and press Enter. A message will come up telling you you've got a friend card. Going to the Second Option under 通信モード, オフラインロビー, you can do ghost battles against them (First available option on the card, ゴースト対戦).
By the way, to make sure cards don't get bumped out of your lobby by other cards (in case you somehow manage to meet 50 other Dissidia players. lol).
Here's the Friend Card Codes(make sure you put them in in all caps):
Yuffie (Uses Level 45 Cloud): PASS3CH3GC45
Shantotto (Uses Level 31 Shanttto): 469J3ELEVENWS
Ahriman (Uses Level 52 Cloud of Darkness): MAPE5REPE4T5
Behemoth (Uses Level 74 Emperor): PASS3SU433KA
Matoya: M8ATK2TCPAYA
Death Machine: CH4D9EN3A3TE3
Ming-Wu: MR3ZNNGXU72PNinja: H4NA53NJRE9
Red Wing: 6A3K2A538TS
Fusoya: SF5AUS5WUJ39Y
Gilgamesh: GU3RK3UG4AMP
Omega: 6C6M6E6G6A6
Oltoross: 8TA9CQQTAC
Siegfried: FGR3ET5KKJC
Cait Sith: P2KET4DTCW6
Ragna: RJAGH5UE6NA7
Seifer: SME4SA39SFAH
Steiner: A3NASX6UXT7
Vivi: VTS3RAPLVKE3
Wakka: WRKA3KUMKRA
Auron: AK6ATR7ECD8N
Basch: LAXBU6GRA4U
Some codes for "recipe" items:
Taurus Recipe: KRCYGU7RJ8E3
Aries Recipe: 33MKERDTA2AK
Gemini Recipe: H3CSH3SDA3YUN
Cancer Recipe: SSAYECXK4CY6
Leo Recipe: HA3SESGAH3W3A
Virgo Recipe: ECTLMCCW3NMCLibra Recipe: TGALKCAWTNA
Scorpio Recipe: H336DETYA23X
Sagittarius Recipe: UC6H3M3778CH3
Capricorn Recipe: UC5H3J46F3MZAAquarius Recipe: MZCC3H38ZTUK
Pisces Recipe: QTAK5UWATGA
If you find more, post them please. I'll add them to the top. XD