Note: Fake, prop books used in the show are not included in this list.
Episode 1: "Work That Body for Me"
Piper: Funny Girl by Nick Hornby
Yoga Jones: High Fidelity by Nick Hornby
Episode 2: "Power Suit"
Black Cindy: What Makes Sammy Run? by Budd Schulberg
Red: My Beautiful Ballooning Heart by Janice Silverman Rebibo
The rest of the books in the pile seem to be prop books.
Episode 3: "(Don't) Say Anything"
Taystee: A Song of Ice and Fire series by George R. R. Martin
Poussey: Bad Kid by David Crabb
Poussey: The Longest Way Home by Andrew McCarthy
Episode 4: "Doctor Psycho"
Red: Essentials of Classic Italian Cooking by Marcella Hazan
Suzanne: Dhalgren by Samuel R. Delany
Episode 5: "We'll Always Have Baltimore"
Abdullah: Emotional Intelligence 2.0 by Travis Bradberry and Jean Greaves
Poussey and Soso: books by Rainer Maria Rilke
Aleida: Trigonometry Essentials Practice Workbook with Answers by Chris McMullen and McGraw-Hill Education Science Workbook for the GED Test
GED® Math Test Tutor by Ms. Sandra Rush M.A.
Poussey: Pêcheur d'Islande by Pierre Loti
Different edition but same book.
Episode 6: "Piece of Sh*t"
Maria: James Bond series by Ian Fleming
Maritza: Goldfinger by Ian Fleming
Black Cindy: Americanah by Chimamanda Ngozi Adichie
Hapakuka: How to Stop Worrying and Start Living by Dale Carnegie
Black Cindy and Abdullah: Going Clear: Scientology, Hollywood, and the Prison of Belief by Lawrence Wright
Judy King: Bird by Bird by Anne Lamott
Episode 7: "It Sounded Nicer in My Head"
Angie: The Lion, the Witch, and the Wardrobe by C. S. Lewis
Nicky and Big Boo: The Lord of the Rings trilogy by J.R.R. Tolkien
Episode 8: "Friends in Low Places"
Bayley: The Wise Man's Fear by Patrick Rothfuss
Bayley: The Name of the Wind by Patrick Rothfuss
I'll Be Seeing You by Mary Higgins Clark
Prescription for Excellence by Joseph Michelli, The Strain by Guillermo Del Toro and Chuck Hogan, and The Iliad by Homer
Death Comes to Pemberley by P. D. James, Our Endangered Values by Jimmy Carter, and The Discipline of Teams by Jon R. Katzenbach and Douglas K. Smith
Julius Caesar by William Shakespeare
Red: Wasted: A Memoir of Anorexia and Bulimia by Marya Hornbacher
Caputo: Cool Hand Luke by Donn Pearce
Episode 10: "Bunny, Skull, Bunny, Skull"
Blanca: Guinness World Records
Sister Ingalls: The Holy Bible: King James Version
Suzanne and Taystee: The Wizard of Oz series by L. Frank Baum
Episode 11: "People Persons"
Suzanne: The Hobbit by J.R.R. Tolkien
Bayley and Coates: It by Stephen King
Judy King: Kitchens of the Great Midwest by J. Ryan Stradal
Episode 12: "The Animals"
Lorna: Sherlock Holmes series by Sir Arthur Conan Doyle
Episode 13: "Toast Can't Never Be Bread"
Suzanne: Emma by Jane Austen, The Silmarillion by J.R.R. Tolkien, and Lord of the Flies by William Golding
The Forgotten Affairs of Youth by Alexander McCall Smith
Moby-Dick by Herman Melville, To Kill a Mockingbird by Harper Lee, and The Magic Mountain by Thomas Mann
Dwight: Lord of the Flies by William Golding (again)
Different edition, same book.