This lists all the collectibles in the order they appear, I take no credit for any of this, I merely cut and pasted the information from other threads on x360a, and added a word here and there to make it easier to follow. If you want to see the original threads, or to leave a much deserved thanks to the creators, they are here:
The first 22 cell phone locations by forum user Rotary Blaze:
The last 28 cell phone locations by forum user Gooseboxer:
The 27 cameras/turrets locations by forum user rotorschnee:
The weapons locations (from the guide) by forum user YouStayClassy:
(7 Phones, 5 Weapons)
W1. [TS5-M4] You start the level with this weapon.
W2. [.40SS] You start the level with this weapon.
W3. [Stun Gun] You start the level with this weapon.
P1. [Adios] This is located northeast of the Lincoln Memorial almost between two pillars.
W4. [KFM 03] Dropped by enemies in level.
P2. [I Am El Arma] This cell phone may require a little bit of searching. It is dropped by one of the terrorists in the battle at the beginning of the stage. So it's in open area where the helicopter crashes.
(Be advised that you cannot back track to this location when you move onto the next area, fire will be blocking you from returning. You will come back to this point later in the level so there is no need to restart the level.)
W5. [M70] This is the sniper rifle you pick up just after the helicopter crashes.
P3. [All Assaults Green] In the area where you have to snipe the two RPG gunners. Kill a man with a hoodie and he will drop it.
P4. [Delgado DUI] After (it was before on my play) killing the RPG gunner on top of the Lincoln Memorial (4th gunner), three enemies will attack you as you move north. One of them will have the cell phone. He is wearing an orange vest.
(Be advised that once you start to go north of the Lincoln Memorial in a narrow walkway, a fire will block your path from returning to the earlier part of the level until you kill the RPG gunner at the LCD screen.)
P5. [Reacquire Targets] After passing through a narrow path, you will see a bunch of stacked red boxes. There is a dead SS agent leaning on a metal fence. Northwest of him is a tent. Inside the tent there is a control panel, the cell phone is on top of it.
P6. [Canisters] After killing the 5th RPG gunner, follow the path until you begin moving east again. There will be four portable toilets in the vicinity and a trailer on your left when you are facing east. Enemy will attack in this narrow area. One of them has the cell phone.
P7. [Earn Every Penny] When you return to the Lincoln Memorial, there will be four terrorists in a gunfight with the rest of the SS agents. One of them has the cell phone. If you can, search their body after you have killed one of them. Once you have killed all of them, the level will end quickly. So you must rush to the cell phone and pick it up. If you miss it, you have to restart the level.
(4 Phones, 3 Weapons)
W1. [Grenade] You start the level with this weapon.
W2. [UZI] Dropped by enemies on level.
P1. [Target Number Two] At the beginning of the level you will get a prompt to press LB to throw a grenade. You will encounter enemy here. Once they are taken care of, the first room on the left is a small office. The cell phone is on top of the desk.
W3. [CQC 800] Found in the office on the right (opposite the room with P1).
P2. [Reservations] After hacking the door open, you will be attacked by three men. One of these has a cell phone.
P3. [Building's wired] In the room northeast of the bomb you have to diffuse. The room is green. The cell phone is on a bench.
P4. [Vargas's Speech] After diffusing the bomb you will come to a large room with a T shaped stair case. You will be attacked by enemy soldiers here. One of them has the cell phone.
(6 Phones, 2 Weapons)
P1. [Lost Control] In the hallway with the three fire extinguishers, you'll come into contact with an enemy that is carrying the cell phone.
W1. [CAWS 50] Found in the office on the Filibuster level (I got mine off one of the first guys you come to).
P2. [Inner Circle] After you diffuse the first bomb, follow the wires until it goes into a wall. Now face south and you will see the cell phone sitting on the pedestal of the bust. There is a grenade on the ground to the left.
P3. [Not the Senate Chambers] When you come to a long set of fancy stairs, you will be attacked by three men. One of them has the cell phone.
W2. [17A1] Found by the large stairs (same stairs as P3).
P4. [For Guadalupe] In the circular room where you get ambushed by guys on the ground floor and from guys above. Kill one of the guys with the shotgun. He's usually on the left side.
P5. [Explosives Discovered] In the same room as #4. It is on a bench to the southwest.
P6. [Past, Present or Future] When you drop down in a circular room, one of the terrorists here has it.
(5 Phones, 1 Weapon, 7 Cameras/turrets)
C1. end of tunnel you get night vision in, but right before the elevator. In a room with a red barrel and a sign that points right and says “M2M1”.
P1. [Diplomacy of Death] After going down the elevator and arguing with your superior. You will come to a tunnel with a rail car. In this tunnel, east of the rail car is a control room. The room to the south east of this has a small control panel in the middle of the room. The cell phone is on top of this control panel.
P2. [Wichita] Follow the rail/track until you get to an electric fence. you can go either left or right. Go right and you will reach a room with a few boxes and enemies. There will be two men on a slightly higher level on the north side of this room. There are also two double doors here. You can reach this by jumping on the boxes. One of the guys you killed had a cell phone.
W1. [RPG] Found in the room full of boxes, same as P2.
P3. [Garfield] After the last cell phone, move to the next room to the south. Clear the enemies and go up onto the catwalk. You will see it to your north once you get onto the catwalk.
P4. [Who Are They Talking To?] After tripping the laser which closes the door, you will be back in the tunnel with the rail cars. As you move southwest along the tunnel, there will be a room on your right. When you enter this room, the cell phone will be on the left side.
C2. Past the double doors you hack to open to the hall full of lasers. Right adjacent to a computer terminal you have to hack to open the fence door.
C3. Right behind the computer next to the 2nd turret.
C4 and C5. After hacking the computer, one on each side of the fence door that opens. Right after C3.
P5. [Invaded by Costa Sentava] You will reach a point where there are 4 turret cameras (C2-C5) and you have to hack a computer to open the electric gate. After opening the gate, you will see it on top of some boxes as you pass through the gate.
C6 and C7. Down the hall from the C4 and C5, in a small area with lasers and a sign marked “Storage A1-3”.
(2 Phones, 8 Cameras/turrets)
C1 and C2. right when you start the level. They are at the end of the hallway but move up to you.
P1. [Pinned Down] this phone is dropped in the darkened room after you kill the enemy.
C3 and C4. Fail the first computer you have to hack twice. It’s located after the dark corridors.
C5 and C6. Right after opening the door that triggers the 3rd and 4th turrets. Proceed down the hall but before jumping over the fence: they move toward you.
P2. [Black and White Politics] after the 3rd terminal, go through the tripwire beam rooms and you will end up in the Missile Silo room. Go down the second set of stairs and the phone is on the corner of the platform.
C7 and C8. In “Storage Area C1”, the dark area at the end of the level.
(4 Phones, 12 Cameras/turrets)
P1. [The Smell of Conspiracy] after you taser the open room of agents, go up the stairs and the phone is sitting on top of the desk in the northwest corner room.
P2. [Shut Him Up] after the checkpoint, you will enter a room with four turret cameras. The phone is sitting on top of a tarp covered crate at the base of the far stairs hugging the wall.
C1, C2, C3 and C4. In large room near the beginning (same as P2), labelled as “Supply Depot A”. One in each corner.
C5, C6, C7, and C8. In the dark hallway between “Supply Depot A” and the turntable room.
P3. [Bead on Pierce] after you clear the turret and tripwire beams in the tunnel, you will be engaged by agents. You will be in the train depot chamber. One of the agents you taser will drop the phone.
C9 and C10. After flipping the turntable switch the first time and crawling under the tracks on the way to the “Power Systems Cooling” room. At the start of the dark rail tunnel.
C11. Up the stairs at the end of the dark hall with the laser mines on the way to the “Power Systems Cooling” room.
C12. After jumping the fence from the ceiling duct work in the room with the fans, at the start of the dark hall on the way to the generators.
P4. [Embassy on Fire] after returning to the train depot chamber once you re-power the grid, you will go in a tunnel with many agents. One will drop the phone when tasered. It’s right before the staircase with all the white house signs.