Kino Der Toten may not seem like a Nazi Zombie map where you can camp, however, there are numerous places where you can with success. One of those places is near the double tap perk. You will need 4 players to do this though, even though 3 might be sufficient. This can NOT be done with less than three players because you will likely be over run by zombies. So make sure you have a team of 4 players while 3 may work, but it will depend on what weapons you get.
First off, you will need to open the upper right double doors in the lobby room. This is the only option to go because you can NOT open the door to double tap(or door to the alley way) as it will be used to block zombies. You will need to go around the map the long way. Obviously, you will need to make some points before you can open the barriers to get to the theater.
Once you arrive on the theater stage, open the door at the other end. Proceed up the stairs where you will arrive in a small room. This room has a couple barricades, and has stairs leading down to the alley way. There is a gate that needs to be opened. Open the gate and go through the alley way until you see the double tap perk. DO NOT OPEN THE DOOR ON THE SMALL STAIRS!(near double tap, and barricade) This will be the door that blocks zombies from coming in that direction. This is why you needed to go around the whole map. Never open this door.
Now, you are in a great defensive position. One player needs to guard the barricade in the back as zombies will come through it. Sometimes there will be a lot. The three other players need to stand in front of the small stair case. However, one player can stand on the stairs if he or she wishes. Just make sure you, or that player does not accidentally open the door.
The player with the weakest guns should guard the window. The window is also good for someone who carries a shotgun. Shotguns are very effective for guarding windows.
The other players should be defending the front with assault rifles, machine guns, and etc. If one person has a ray gun, they should stay further back. There should be at least one player in the front. This spot is very good to defend, but make sure you get crawlers. This will enable you to go buy perks you need, or upgrade your weapons.
This concludes the tutorial for Black Ops Zombies Kino Der Toten - double tap camping spot. Hope this helps.