Pemberton: Down the hallway in the same building as the sheriff.
Garwater: Inside the firestation when you enter through the door on the far left it's in the second room (next to the room with the squirrel in it).
Fontana: In the diner. Go around the outside of the counter, and its on the wall to the right. Directly opposite of the left door.
Cleburne: Once you get to the lighted nurses station that's in a corner, go down the long hallway to the right. The last door on the right has the poster laying flat on a desk beside the patient's bed.
Taggart: In the projector building. If your facing the counter, look left. It's the bearcats 31 poster.
Lafferty: After talking to Noah, go through the grocery store to the back right. At the locked door a zombie will break through. Inside that room is the poster.
Archer Creek: When (guy) says to "get in, snipers on the roof" enter the door to the left of the blue car. It's the second building from the left. The poster is straight ahead.
Sherwood: Inside the house with a black car parked in the driveway. It's in a bedroom in the back with the lights on.