hey, if u want some really good weapons, and i mean AWESOME WEAPONS, just go through the areas looking for red lights on the roof and shoot them and a new area will open up! its usually in the quiet areas were there are no enemies. PLEASE PLEASE PASS THIS ON! (credit to helmuth)
you have to shoot all cards on every level to get bonus. here is where cards are: Level 1: right beside the guy on the trash can. level 2: in one of the seats to the left of your target. level 3: in the palm tree, slightly hidden. level 4: on the car door. Note that you can kill the man and then shoot the card on this level, unlike the rest, where the card dissapears. level 5: on the box behind your agent. level 6: to the lower left of your target. you will probably have to shoot the card, then fail the mission for this. dont worry, if you fail the mission after shooting the card, the card will still be counted. level 7: Below the target right next to the podium. level 8: at the top-right corner of the banner that says "propaganda is truth" level 9: near the bottom-left of the screen where there are 3 spray-painted cards. Thats all of them! keep this message alive so nobody else has to write this.