The "Space Ship" achievement is in the same level as the "Dead Alien", the space ship can be found on a dune that's between the oasis and the Egypt Temple, closer to the oasis and to the left of the Temple if you are facing the front of the temple. The "He Was Here" achievement can be found in the level where you escape Carlos' men after being captured, its in an alley way, somewhere before the section where you go under the road to get to the next section, the achievement pops after you look at the red text in the alley way. The "Respect" achievement is found near the boat dock before you go to Pirate Island, the achievement pops after you look at some red text on the wall of the building furthest to the right when you enter the level after hopping off the train.