Here's all the know codes and colors (I added the formatting and colors myself I didn't copy and paste, but I didn't find any of the codes myself I have various sources I also posted this list in the gamefaqs forums under the name "ExplodingCactus") I take pride in it being the most complete and well edited list I have come across thats why I started making it two weeks ago because I couldn't find any well organized lists and got sick of it.
Number / Code / Source / Color / System*
T-Shirt 1 = 73154986 - Red Weekly Famitsu - (Red)
T-shirt 2 = 94372143 - Xbox360 - (White) - Xbox Only
T-Shirt 3 = 69088873 - Midnight Live 360 - (White) - Xbox Only
T-shirt 4 = 40358056 - Den Geki - ??? - PS3 Only
T-shirt 5 = 96725729 - Yellow Den Geki - (Yellow)
T-shirt 6 =
T-shirt 7 =
T-shirt 8 = 63152256 - Digimonostation.jp - (Black)
T-Shirt 9 = 34297758 - Weekly Playboy - (Hot Pink)
T-Shirt 10 = 88020223 - Blue Famitsu.com - (Cyan)
T-Shirt 11 = 25060016 - 4Gamer.net - (Dark Green)
T-Shirt 12 = 65162980 - Hall's Original Costume RARE CHEMISTRY - (Purple+Tan)
T-Shirt 13 = 56428338 - ??? - (Blue)
T-Shirt 14 = 18213092 - WCP Baseball Cap - (Green)
T-Shirt 15 = 26797358 - ??? - (Face, White with Green Sleeves)
T-Shirt 16 = 71556463 - ??? - (Bullet Bull thing, Purple)
T-Shirt 17 = 31354816 - ??? - (Person Holding Gatling Gun, White)
T-Shirt 18 = 12887439 - StreetJack - (Light Blue)
