East Pump Station - 1 roll in a toolbox on the top shelf of the rack behind the terminal (random - must be stolen).
HELIOS One - 3 to 5 rolls (plus an equal number of wrenches and scrap electronics) can be found on shelves and in toolboxes in the Solar Collection tower. See That Lucky Old Sun for details on gaining entry and hostile robots/turrets.
Hell's Motel - 2 rolls on the shelf against the back wall, and on the second floor in the cabinet.
Big MT north tunnel - 3 rolls on the middle shelf of the rack in the room directly right when you enter the place, behind the door. Old World Blues (add-on)
X-13 research facility - 1 roll can be found behind the force field when you enter the place on the right, on the middle shelf of the first rack on the left, and 5 rolls are present behind an average lock door on the first level. Old World Blues (add-on)
X-13 research facility (testing facility) - 1 roll can be found on a table, when you enter the testing facility take the door on your right few meters in front of you. Old World Blues (add-on)
Hopeville missile silo bunker - 3 rolls can be found on the bottom shelf of a rack behind a locked door, unlockable through a easy terminal, near a destroyed eyebot; 1 roll at the top of the stairs, when you leave the room with the missile, between 2 shelves of a fallen rack; 1 more in the same room, behind a fallen chair; continue upstairs to the Storage room, and on your right in front of a rack there will be another one. Lonesome Road (add-on)