Ann O'Bannon (Romance) Constance O'Banyon (Romance) Nancy O'Berry (Romance, Historical Fiction, Erotica) Thomas F. O'Boyle (Business) Anne O'Brien (Romance) Cormac O'Brien (People, History) Francis A. O'Brien (History) Glenn O'brien (Self Improvement) Irene O'Brien (Romance) Kathleen O'Brien (Romance) Lija O'Brien (Erotica) Priscilla Y. O'Brien (Dark Fantasy) Randy O'Brien (Historical Fiction) Sean O'Brien (Science Fiction, Sports/Entertainment) Siondalin O'Chnoc (Erotica) Glenys O'Connell (Romance) Matthew S. O'Connell (Business, Reference) Robert L. O'connell (History) Patricia T. O'Conner (Reference, Young Adult) Amy O'Connor (Erotica) Catherine O'Connor (Romance) Francis G. O'Connor (Health/Fitness) Joseph O'Connor (Mainstream, Historical Fiction, Self Improvement) Kaitlyn O'Connor (Erotica) Kathleen O'Connor (Mystery/Crime, Romance) Kevin O'Connor (Business) Mary O'Connor (Romance) Michael O'Connor (Romance) Philip O'Connor (Mainstream) Richard F. X. O'Connor (General Nonfiction, Business, Self Improvement) Sasha O'Connor (Romance) Deirdre O'Dare (Erotica) Constance O'Day-Flannery (Romance) Bill O'Dea (Science Fiction) Brian O'Dea (People) A. J. O'Dell (Romance) Kathleen O'Dell (Young Adult) Tawni O'Dell (Mainstream) Kristin O'Donnell Tubb (Young Adult) Jodi O'Donnell (Romance) Kathleen O'Donnell (Travel) Kelly O'Donnell (Erotica) Kristina O'Donnelly (Mainstream, Romance, Historical Fiction) Brian Patrick O'donoghue (Humor) John O'Donohue (Mainstream, Spiritual/Religion, Self Improvement) Mike O'Driscoll (Horror) J.L. O'Faolain (Erotica) Leslie O'Grady (Romance) Scott O'Grady (Children's Fiction) Redmond O'hanlon (Travel) Nancy O'Hara (Self Improvement) Claudine C. O'hearn (General Nonfiction) Alexandra O'Hurley (Erotica) Richard O'Kane (History) Allan O'Keefe (Horror) Bobbie O'Keefe (Romance) Kerrie O'Keefe (Erotica) Molly O'Keefe (Romance) Susan Heyboer O'Keefe (Mainstream, Spiritual/Religion, Children's Fiction) Michael O'Keeffe (Sports/Entertainment) Gene O'Kelly (Self Improvement) Janeen O'Kerry (Romance) Laura O'Leone (Romance) Tierney O'Malley (Romance, Erotica) Alex O'Meara (Mainstream) Stewart O'Nan (Mainstream, Sports/Entertainment, History) Barbara O'Neal (Mainstream, Romance) Eilis O'Neal (Young Adult) Eugenia O'Neal (Historical Fiction) Rory O'Neal (Erotica) Brian O'Neil (Sports/Entertainment) Heather O'Neil (Children's Fiction) William J. O'Neil (Personal Finance) Anna O'Neill (Erotica) Gene O'Neill (Science Fiction, Horror, Fantasy, Dark Fantasy, Erotica) Ian O'Neill (Suspense/Thriller) Joseph O'Neill (Mainstream, People) Michelle O'Neill (Science Fiction, Erotica) Erin O'Niall (Erotica) Bill O'Reilly (Suspense/Thriller, Young Adult, Politics/Government) Kathleen O'Reilly (Humor, Mainstream, Romance) Katy O'Reilly (Romance, Erotica) Morgan Q. O'Reilly (Romance, Erotica) Terry O'Reilly (Erotica) Wynter O'Reilly (Erotica) Erin O'Riordan (Fantasy, Erotica) Brian O'Rourke (Suspense/Thriller) Frank O'Rourke (Fantasy, Romance) P.A. O'Rourke (Spiritual/Religion) Perri O'Shaughnessy (Mainstream, Suspense/Thriller) M. J. O'Shea (Erotica) Patti O'Shea (Science Fiction, Dark Fantasy, Romance) Sandrine O'Shea (Erotica) Stephen O'Shea (Spiritual/Religion) S. K. O'Toole (Mystery/Crime) Sonnet O'Dell (Horror, Fantasy, Romance) Natasha Oakley (Romance) Joyce Carol Oates (Mainstream, Romance, People, Reference, Young Adult) Barack Obama (People, Politics/Government, History) Rita Oberlies (Romance) Mauricio Obregon (General Nonfiction) Illian Obsidian (Erotica) Kathleen Odean (Reference) Terry Odell (Romance, Erotica) John Oden (Sports/Entertainment) Sally Odgers (Fantasy, Mainstream, Romance, People, Young Adult) Gene Odom (Sports/Entertainment) Mel Odom (Fantasy, Dark Fantasy, Suspense/Thriller, Spiritual/Religion, Young Adult) Shawn Oetzel (Fantasy) Jenny Offill (General Nonfiction, Personal Finance, Children's Fiction) Lloyd John Ogilvie (Spiritual/Religion) Madeleine Oh (Erotica) Alix Ohlin (Mainstream) Kenichi Ohmae (Business) Barbara Milo Ohrbach (Self Improvement) Beatrice Ojakangas (General Nonfiction) Bayo Ojikutu (Mainstream) Willa Okati (Romance, Erotica, Gay Fiction) Jennifer Oko (Romance) Arika Okrent (General Nonfiction) Josie Okuly (Romance, Children's Fiction) Olaf Olafsson (Mainstream, Historical Fiction) Marvin Olasky (Spiritual/Religion, Politics/Government) Keith Olbermann (Politics/Government) Tom Olbert (Horror) Marnie Old (General Nonfiction, Reference) Elizabeth Oldfield (Romance) Sara V. Olds (Romance, Historical Fiction) Sharon Olds (Mainstream) Anne Oliver (Romance) Dave Oliver (History) Gloria Oliver (Fantasy, Young Adult) Jana G. Oliver (Fantasy) Marina Oliver (Romance) Mary Oliver (Mainstream) Richard W. Oliver (Business, Technology/Science) Stephanie Stokes Oliver (Health/Fitness) Buster Olney (People, Sports/Entertainment) Brad Olsen (Travel) Gregg Olsen (Suspense/Thriller, True Crime, History) Nora Olsen (Young Adult) T. V. Olsen (Politics/Government) Barbara Olshansky (Politics/Government) Gary W. Olson (Dark Fantasy) Jeff Olson (Business) John B. Olson (Suspense/Thriller) Lew Olson (General Nonfiction) Lynne Olson (Erotica, History) Jerry Oltion (Science Fiction) Robert Oman (Education) Michael Ondaatje (Mainstream, Sports/Entertainment) Robert Onopa (Science Fiction) Adrian Onyando (Mainstream) Jeff D. Opdyke (Business, Personal Finance) Linda Opdyke (Romance, Suspense/Thriller) E. Phillips Oppenheim (Mystery/Crime, Suspense/Thriller, Classic Literature) Edward Phillips Oppenheim (Historical Fiction) Jerry Oppenheimer (People) Options Institute (Business) Daniel Oran (Mystery/Crime) Robert Orben (Humor) Terri L. Orbuch (Family/Relationships) Sandra Orchard (Romance) Alicia Night Orchid (Erotica) Baroness Orczy (Mystery/Crime, Alternate History, Romance, Suspense/Thriller, Historical Fiction, Classic Literature, Young Adult) Ram Oren (History) Fran Orenstein (Young Adult) Adera Orfanelli (Erotica) Neale Orinick (Fantasy) Doreen Orion (Travel) Dael Orlandersmith (Suspense/Thriller) Linda M. Orlando (Romance, Young Adult) Susan Orlean (Travel, Politics/Government) Ilo Orleans (Children's Fiction) Carol Orlock (Fantasy) Erica Orloff (Humor, Romance, Suspense/Thriller) Judith Orloff (Self Improvement, Health/Fitness) Suze Orman (General Nonfiction, Business, Personal Finance) Dr Dean Ornish (Health/Fitness) Dean Ornish, M.D. (Health/Fitness) Jenny Orosel (Fantasy) Alice Orr (Romance) Wendy Orr (Young Adult, Erotica) Zelma Orr (Romance) Julie Orringer (Mainstream) Carol Orsborn (Self Improvement) Nancy Ortberg (Business) Annmarie Ortega (Romance, Erotica) Maureen Orth (True Crime) Jani Ortlund (Spiritual/Religion) George Orwell (Mainstream, Classic Literature) Sara Orwig (Romance) Elane Osborn (Romance) Kevin Osborn (Education, Health/Fitness, Family/Relationships) Ross Eddy Osborn (Horror) Shane Osborn (Politics/Government) Stephanie Osborn (Science Fiction) Frances Osborne (People, History) Larry Osborne (Spiritual/Religion) Maggie Osborne (Romance, Historical Fiction) Mary Pope Osborne (Children's Fiction, Young Adult, Children's Nonfiction) Richard Osborne (General Nonfiction) Sarah Jane Osborne (Romance) Stephen Osborne (Erotica) Tom Osborne (Self Improvement) Micky K. Osburn (Romance) Tamia Dawn Osburn (Science Fiction, Romance) Charles Osgood (Humor, Politics/Government) Patricia Oshier-Bruening (Erotica) Osho (People, Spiritual/Religion, Self Improvement, Health/Fitness, Family/Relationships) Nina M. Osier (Science Fiction, Mainstream, Romance, Family/Relationships) Jack Osprey (Erotica) Jerry Oster (Mystery/Crime) Dori Ostermiller (Romance) Chris Ostrowski (Technology/Science) BF Oswald (Mainstream) Teryl Oswald (Romance) Steve Otfinoski (People) James P. Othmer (Mainstream, Business) Kathy Otten (Romance) Randy Ottinger (Business) Judith Otto (Romance, Young Adult) Ian Ousby (History) Stephen Overholser (Children's Fiction, Politics/Government) Wayne D. Overholser (Politics/Government) Jeffrey Overstreet (Fantasy) Ariana Overton (Fantasy, Mystery/Crime, Romance, Suspense/Thriller, Children's Fiction) Elaine Overton (Romance) Max Overton (Fantasy, Mystery/Crime, Suspense/Thriller, Historical Fiction, History) Chris Owen (Erotica) Marjorie Owen (Mystery/Crime) Timothy Owen (Erotica) Anthony Owens (Horror) Cynthia Owens (Romance) J. C. Owens (Erotica) Michele Owens (Business) Parker Owens (Young Adult) Robin D. Owens (Science Fiction, Fantasy, Mainstream, Romance) Terry Owens (Family/Relationships) Zahra Owens (Erotica) An Owomoyela (Science Fiction) Noelle Oxenhandler (People) Oxford University Press (Education, Reference, Family/Relationships) Helen Oyeyemi (Mainstream) Bev Oz (Romance) Barry Ozeroff (Mainstream) Mark Ozeroff (Historical Fiction)