Some of you might have seen that Dustloop fired up a wiki for Persona 4: Arena not too long ago and it's already full of great info for the game. You can find everything from frame data to combos here, not to mention hitbox images for attacks for each character as well. You can simply click where it says "hitbox" to the right of each attack to check it out.
Beyond that there are full zip files for each character if you'd like to quickly scroll through their attacks. Check out each character after the jump.