Just before entering the prison, you’ll see these stairs. Two enemies attempt to escape up them. Head up yourself and find the laptop hidden at the shadowy far end of the room.
The Gulag - Intel Item #2
This laptop is at the back of the first circular, central control tower. Just go around the monitors and you can’t miss it.
The Gulag - Intel Item #3
This one’s in the section where Soap tells you to grab a Riot Shield… immediately after the second control tower in which you were locked in and surrounded by enemies. Simply follow the mission path and check the prison cells on your right. In the one pictured below, you’ll find the laptop.
The Gulag - Intel Item #4
You’ve located Prisoner #627. The game’s characters are urging you to run forward and escape the mission. Don’t… not yet. Immediately after the cutscene ends, turn around and check the desk behind you, to the right of the door you came through. Grab the laptop and then you can follow your pals.
Get inside the government building and clear the lobby area of enemies. Then follow your men down this hallway and check the elevator on your left. A laptop is sitting between the two dead soldiers... you might have to jump and crouch over the first body to grab it, though.
Of Their Own Accord - Intel Item #2
This laptop is near the balcony with the missile launcher you plant C4 on. A Russian soldier will pop out of the door indicated below. Kill him and move inside for the intel.
Follow Captain Price until you reach an elevated pipeline. He'll give you the option of shooting or sparing two guards at this point. Kill them and check the area to their left. Underneath a downed parachute is the laptop.
Contingency - Intel Item #2
Find Warehouse #33 and check all the workbenches inside. One of them, near one of the doors, holds the laptop.
Contingency - Intel Item #3
This laptop is next to the helipad, which depending on your aim with the Predator missiles, may or may not have the actual helicopter sitting on it. Check the wall opposite the landing area.
Whiskey Hotel - Intel Item #1
You should see this one immediately after exiting the Oval Office. It's on a black leather sofa right outside the door.
Whiskey Hotel - Intel Item #2
Near the end of the mission, just after running up the stairs pictured below but before lighting your green emergency flares, check the right wall for a laptop.