Right know we have minecraft 1.5.1 so if you downloaded minecraft 1.5.2 TMI then go back and download 1.5.1 TMI and also force update minecraft by pressing Minecraft.exe > Options > Force Update > Done > Login. Delete META-INF in minecraft.jar. It also looks like you have minecraft 1.3_01?! It says that! Update minecraft then tell me if my instructions work. Make sure to click TMI 1.5.1!
Please download mods only from their official source, instead of downloading them from third party sites that do not have permission from the mod authors. You can find the official thread for the Too Many Items mod here.
Private Mod Note
Rollback Post to RevisionRollBack
Please quote my post if you want to make sure I would read it.