Scholar eBook Locations
There are 29 "Scholar" eBooks in Deus Ex: Human Revolution, each of which provides some background on the game world and give a +200 XP bonus upon you finding them. Collecting all of them will earn you the "Doctorate" achievement. Below, you'll find the locations of all of them, arranged by area and ordered roughly chronologically as you'll find them throughout the game.

Scholar eBook #1 Detroit - Sarif Plant Server Room

"Neural Interface Protocols: The PEDOT Revolution": As you near the Server Room, you'll come across a security station and a Turret. Dodge past the Turret and into the security station, then look for a cardboard box on top of a crate - pick it up to reveal this first Scholar eBook.
Scholar eBook #2 Detroit - Sarif Plant Admin Building

"Artificial Muscles": Immediately before bursting into Josie Thorpe's office to confront Zeke Sanders, check her secretary's desk near the door to find your second Scholar eBook.
Scholar eBook #3 Detroit - Sarif Industries

"The Nature of Neuroplasticity": You'll encounter this third eBook after returning to Sarif Industries from the Sarif Plant mission. Head on in to Pritchard's office, the Tech Lab on the second floor, and this eBook should be in plain sight on the table behind his desk.
Scholar eBook #4 Detroit - Sarif Industries

"The Tyranny of Biology": Head over to Office 25 on the second floor and hack the door's keypad to find this Scholar eBook waiting on a coffee table. Alternately, you can open up Office 27 with the code "4145" and then use the ventilation duct to reach Office 25.
Scholar eBook #5 Detroit - Sarif Industries

"The Neural Hub - Design for a Next Generation": Check out Office 27 to find a Scholar eBook on the coffee table. You can get into Office 27 either by using the code "4145" on the door keypad, or by hacking into Office 25 nearby and climbing through the vent.
Scholar eBook #6 Detroit - LIMB Clinic

"The Visual Cortex 2.0 - The Eye, Redesigned": When you visit the LIMB Clinic to meet with Dr. Marcovic, take the door out of the lobby into the back hallway. You'll find the Scholar eBook on a trolley just before reaching the second operating room.
Scholar eBook #7 Detroit - South Apartments

"Nano-Augmentation: Pipedream, or Theory for the Future?": If you rescued Josie Thorpe at the Sarif Plant, you'll later be asked by her husband, Greg, to visit them at their apartment, the southernmost building of the four. Head up to their second floor and you'll find this eBook on the nightstand in their bedroom. Note that if you didn't rescue Josie, you'll need to hack the level 1 keypad on the front door to get in.
Scholar eBook #8 Detroit - West Apartments

"The Arms (and Legs) for Man - The Structure of Cybernetic Limbs": You'll visit the West Apartments a couple of times during your stay in Detroit, both when dealing with O'Malley and when hunting for Brian Tindall. Take the stairs to the third floor and either hack the level 5 front door, or use the code "2356". Next, either hack or smash your way through the level 2 lock on the bedroom door, and you'll at last find this Scholar eBook in the "docta's" bedroom, next to the computer.
Scholar eBook #9 Detroit - North Apartments

"Respirocyte Technology & Hazardous Environment Parsing": When you're visiting the arms dealer Seurat in the North Apartments (accessed via the fire escape near the basketball court in the Detroit alleys), sneak into his bedroom to find this Scholar eBook on top of a shelf.
Scholar eBook #10 Detroit - Police Station

"The Threat of Cybernetic Discognition Disorder": When breaking into the Police Station to find the hacker's Neural Hub, you'll want to check the mortician's desk for this Scholar eBook, on top of several other regular books.
Scholar eBook #11 Detroit - Chiron Building

"The Intelligence Circuit": When you've stopped by Jensen's apartment in the Chiron Building, whether to plug the Neural Hub into the computer or to pick up O'Malley's bribe money, be sure to check the nighstand in Adam's bedroom for this next Scholar eBook.
Scholar eBook #12 Detroit - Derelict Row

"Vestibular Augmentation and Enhanced Agility Factoring": During your infiltration of Derelict Row, search the basement in the southern building to find this Scholar eBook sitting on top of some barrels.
Scholar eBook #13 Detroit - FEMA Detention Center

"Blurring the Boundaries Between Man and Machine": Before taking the last elevator down to fight Barrett, you'll want to take a moment to check the cafeteria on the way. You'll find a locked lounge room nearby, code "7894", wherein you'll discover this elusive Scholar eBook on the table.
Scholar eBook #14 Hengsha - Youzhao District

"Invasive Brain Machine Interfaces": When you've made it to the Youzhao District in Hengsha, use one of the ladders on the street to climb to the rooftops above, then head to the apartment building on the east end of the floof. Hack or smash your way in, and you'll uncover your prize on the desk in the living room.
Scholar eBook #15 Hengsha - Youzhao District

"The Science and Theory Behind Cochlear Implants": During your stay in the Youzhao District, find the small apartment building in the middle of the district and work your way up to the second floor. Hack your way into the apartment and swipe this eBook out from under its owner's nose.
Scholar eBook #16 Hengsha - Hengsha Court Gardens

"Understanding Vision (Part 1)": During your infiltration of the Hengsha Court Gardens, head to the main plaza outside and break into the apartment immediately to the left of the Court Gardens' front door. You'll find the Scholar eBook you're looking for on the kitchen counter.
Scholar eBook #17 Hengsha - The Hive

"Optical Enhancement Functionality": While exploring The Hive, be sure to stop by the security office at the front door, accessed via the basement tunnels. Grab the Scholar eBook from the desk while you loot the room. Note that this is much more easily accomplished if you managed to persuade the manager upstairs to let you see Tong - otherwise the club's guards will be hostile towards you when they spot you inside the restricted area.
Scholar eBook #18 Hengsha - The Hive

"The Use of Neuromuscular Facilitation Systems": After you've persuaded the manager upstairs to see Tong, make your way to his office in the basement to find this Scholar eBook on the desk at the side of the room. Note: you must get permission to see Tong from the manager to get this eBook, otherwise Tong's office will remain locked for the rest of the game.
Scholar eBook #19 Hengsha - Alice Garden Pods

"Electrogravitic Technology Applications": When you're hunting down the hacker in the Alice Garden Pods, make a stop at Pod 143 in Section 1 to find this Scholar eBook on the bed.
Scholar eBook #20 Tai Yong Medical - Augmentation Storage

"Better than Nature?": Before taking the cargo elevator up to the Pangu from the Augmentation Storage level, look for a vent on the left-hand side of the elevator. You can either lift the heavy crate on the right-hand side of the room and bring the smaller crate over to reach the vent, or use some skillful jumping to get in provided you have the Jump Enhancement. Follow the vent and you'll reach a larger shaft whose ladder is missing. You'll need to use the Icarus Landing System augmentation to fall down there - any other way is lethal. When you've reached the bottom, snatch the Scholar eBook from the floor, along with a bunch of other useful items.
Scholar eBook #21 Tai Yong Medical - Laboratories

"Radical Evolution is a Reality": Once you've been permission to enter the Lee Geng Memorial Lab, or have simply blasted your way in, check the bins underneath the center lab unit in the room to find this easy-to-miss eBook.
Scholar eBook #22 Tai Yong Medical - Penthouse

"Brain Implants": Before leaving Tai Yong Medical from the hangar bay, climb up to the control room on the southwest side of the hangar. You'll spot this Scholar eBook on the front desk.
Scholar eBook #23 Picus Communications - Offices

"HUMAN POWERED - Autonomous Energy Reclamation Systems": Once you reach the newsroom, head to the nearby production room, accessed via the balcony, and search for this Scholar eBook on a counter just outside the storage room.
Scholar eBook #24 Picus Communications - Sub-Basement

"Healing Thyself - Health Preservation Augmentations": Once you reach the large open office area, look around for a separate office in the northwest corner. The Scholar eBook you seek is clearly visible on one of the desks.
Scholar eBook #25 Detroit (Return) - Detroit Convention Center

"Vagus Nerve Stimulators - Repurposing the Technology": Once you've either been given access to the backstage area, or have made your own access, find the small lounge just outside William Taggart's dressing room, and you'll spot this eBook on the coffe table near the television.
Scholar eBook #26 Detroit (Return) - Sandoval's Hideout

"Dermal Modification Process": Hunting William Taggart's aide, Sandoval, you'll eventually run into him in his office hidden deep inside the Detroit sewers. Once you've dealt with him, either socially or with force, snatch this eBook from his desk.
Scholar eBook #27 Hengsha (Return) - Harvesters' Hideout

"Understanding Vision (Part 2)": When breaking into the parking garage that the Harvesters call home, you'll find a small operationg room on the lowest sub-level. The Scholar eBook can be found on a desk next to a computer monitor. If Malik was killed, you'll find her body in this same room.
Scholar eBook #28 Singapore - Omega Ranch

"Delgado and the Stimoceiver": When you've reached the Micro-Gen Lab, make your way to the second floor and find an old disused lab, the one where Sevchenko used to work - you'll need to hack the keypad on the door or use the code "5377". The lab is mostly empty, save for this Scholar eBook on a desk in the back.
Scholar eBook #29 Singapore - Omega Ranch

"Reimagining Retinal Implants: Doctor Dobelle's Success": The game's final Scholar eBook can be found in the Secure Bunker area of Omega Ranch, after you've dealt with Namir. Once you've spoken with Megan, hack into the level 5 locked safe to find what you seek. Congratulations, and enjoy your Doctorate!