Dead Rising 2 for the PS3, Xbox 360, and PC has thirty four Zombrex posters you can spray paint to earn the “Improper Behavior” achievement/trophy. That’s a lot of posters to track down, so luckily Lord Maim over at PS3Trophies.org made this map to help you find them all.
Note that some are only unlocked after certain case progression, and they are marked as such on the map.
Click on the image below to view a much larger version.