The sewers consist of several long interconnecting tunnels which lead into a larger train tunnel. There are several maintenance rooms which hold junk items in them, and some tunnels end in rubble. The main tunnel is guarded by a turret which can be deactivated with a terminal near the entrance. Several raiders are fighting mole rats inside.
The tunnels lead into a generator room, which allows access into a large train tunnel. The tunnel is covered in land mines and several raiders, including Rocksalt, stand guard nearby. There is a small room leading into a living quarter where the raiders sleep. Continuing through the tunnels lead back into sewers where more mole rats live.
Dean's Electronics when you first enter the subway area from the south. Deal with 3 raiders (1 behind sandbags, other 2 in corridor), enter the corridor, turn left, and enter the small room on your left. The book will be on the right corner behind toolbox (near ‘generator’) (A).
In the sleeping room of the raiders is a pre-War book on top of a bookcase (B).
Behind a locked door flanked by a terminal, on a bottom shelf in a wooden crate with some burned books, is another pre-War book (D).
xbox360 There is a rare bug that when you unlock the door using Rocksalt's key and open the door there will still be a barrier like the door was never opened in the first place. The only way to fix is reload a previous save. [verified]
ps3xbox360 If you complete the quest then steal the Repellent Stick (hidden upstairs in Craterside Supply) it will be irremovable as it still counts as a quest item but will not weigh anything. You can use it as a weapon but it cannot be dropped and will not appear in your inventory when checking in a container or a shop. [verified]
xbox360 After entering the tepid sewers an Enclave deathclaw will immediately spawn in front of you, then die in a matter of seconds. This is possibly somehow connected with the deathclaw control scrambler which basically turns Enclave deathclaws into short-term followers. [verified]
xbox360 Once you go into the sewer it's possible you won't be able to get back out due to a door lock glitch. [verified]