Hats Welcome to the 23rd: At the beginning of the level, there should be two sets of oil drums directly in front of you. Destroy the barrels on the left and Tex's Hat should appear.

Rescue Brutus: ???

Cemetery Gates: The hat on mission 3 is located on the roof of one of those huts after you have crossed the pipe over the sludge pool.

Hunting for Shaddon: A hat will appear in the first weapons depot right after you rescue the spy. It'll be in the middle of that room.

Terrorist Ghetto: In the underground area beside the pyramid structure, there will be a computer terminal that only Hawk can access. Right beside that terminal is a toxic waste bucket. Blow up the toxic waste and the hat will appear.

Lonesome Death of Edward Kingman: At the very end of chaper 1, just before jumping off the cliff, the hat will be located at the begining of the wall on the right side inside a small concrete shed. It's right behind the last zombie you'll kill before the second part of the mission begins.

Ship Graveyard: You can find the hat in the middle of this level. Just before a couple of Ferals jump out of the water from hiding, there are 2 or 3 guard towers. The hat is located in the highest guard tower.

Return to Osiris: The hat in level 8 return to osiris lies in one of the huts in chaper 2. The hut is near where one of the energy pipes crosses your path. Follow this pipe from where it is severed(you cross through the gap anyway) where it leads up to the hut which contains the hat.

Seers on the Bayou: The hat is located on the top of the first guard gates (early on in the first chapter).