O   | O Fracas | O Level |
| O Suilleabhain, Micheal | O Toole, Peter | O'Banion, John |
| O'Brien, Conan | O'Brien, Deke | O'Brien, Dermot |
| O'Brien, Erin | O'Brien, Hod | O'Brien, Michael |
| O'Brien, Tim | O'Brien-Docker, Ian | O'Brien-Docker, John |
| O'Bryan | O'Bryant's Washboard Wonders | O'Casey, R. |
| O'Casey, Sean | O'Connell, Helen | O'Connell, Maura |
| O'Connor, Cavan | O'Connor, Des | O'Connor, Hazel |
| O'Connor, Kathie | O'Connor, Sinead | O'Connor, Tom |
| O'Day, Alan | O'Day, Anita | O'Donnell Roger |
| O'Donnell, Al | O'Donnell, Daniel | O'Donnell, Joe |
| O'Donnell, Rosie | O'Dowd, Barry | O'Dowda, Brendan |
| O'Duffy, Michael | O'Farrill, Chico | O'Flynn, Liam |
| O'Gwynn, James | O'Hagan, Sean | O'Hara, John |
| O'Hara, Mary | O'Hara, Mary Margaret | O'Hara, Maureen |
| O'Hearn Patrick | O'Jays, The | O'Kane, John |
| O'Kanes, The | O'Kaysions, The | O'Keefe, Danny |
| O'Keefe, Peggy | O'List, David | O'Meara, Jo |
| O'Neal, Alexander | O'Neal, Johnny | O'Neal, Shaquille |
| O'Riordan, Dolores | O'Rouke, Jim | O'Rourke, Declan |
| O'Rourke, Jim | O'Sullivan, Gilbert | O, Karen |
| O-Town | O. J. Abbott | O.A.R (Of A Revolution) |
| O.C Roberts | O.C. | O.D, Adrenalin |
| O.G.C. | O.M.D. | O.T. Quartet |
| O.T.T | Oak | Oak Ridge Boys, The |
| Oak, Crooked | Oakenfull, Ski | Oakenshield |
| Oakey & Moroder | Oakley, Gee | Oaktown's 3-5-7 |
| Oasis (Dutch) | Oasis (Mary Hopkin) | Oasis (UK) |
| Oasis (US) | Oates John | Oates, Jackie |
| Oath, The | Obernik, Sam | Oberst, Conor |
| Obey The Brave | OBF | Obi |
| Obie Trice | Obituary | Objayda |
| Obliveon | Obraztsova, Elena | Obsession |
| Obus | Ocasek, Ric | Occasion, The |
| Occasional Few, The | Occasional Five, The | Occasional Project, The |
| Ocean | Ocean Colour Scene | Ocean, Billy |
| Ocean, Humphrey | Oceanic | Oceansize |
| Ochil Players, The | Ochs, Phil | Ockeghem, Johannes |
| Octave One | Octavia | October Country |
| October, Gene | Octopus | Odd Man Out |
| Oddie, Bill | Odds & Ends | Odell, Tom |
| Odetta | Odin | Odnoposoff, Ricardo |
| Odrich, Ron | Odyssey | Odyssey |
| Odyssey, The | Of Arrowe Hill | Of Monsters And Men |
| Of Montreal | Ofarim, Esther | Off |
| Off The Wall | Off With Their Heads | Off-Shore |
| Offenbach, Jacques | Offhooks, The | Official Secrets, The |
| Offshore | Offspring | Ofshore |
| Ofwerman, Rune | Ogan, Gary & Lamb, Bill | Ogdens, The |
| Ogdon, John | Ogdon, John & Lucas, Brenda | Ogerman, Claus |
| Ogermann, Claus | Oggum | Ogura, Kei |
| Oh No | Oh No Ono | Oh Ok |
| Oh Well | Oh Wonder | Oh! Polo |
| Oh' Dev | Oh, Atoms | Oh, Nadia |
| ohGr | OHGR WELT | Ohi Ho Bang Bang |
| Ohio Express | Ohio Players | Ohlsson, Garrick |
| OHM | Ohno, Shunzo | Ohno, Yuji |
| Ohnuki, Taeko | Oil Seed Rape | Oingo Boingo |
| OISIN | Oïstrakh, David | Oïstrakh, David & Igor |
| Oïstrakh, Igor | Oizone | OK Go |
| OK Jive | Okay Temiz | Okereke, Kele |
| Okino, Shuya | Okino, Yoshihiro | Okkervil River |
| Okosun, Sonny | Ol Dirty Bastard | Oladimeji & His Talking Drum |
| Olavide, Begoña | Olay, Ruth | OLD |
| Old And In The Way | Old Crow Medicine Show | Old Fashioned Love |
| Old Gold | Old Man River | Old Metropolitan Band |
| Old Mole Band, The | Old Skool Orchestra | Old Skull |
| Old Swan Band, The | Oldfield, Harry | Oldfield, Mike |
| Oldfield, Natasha | Oldfield, Sally | Oldfield, Terry |
| Oldham Tinkers, The | Oldham, Andrew Loog | Oldham, Will |
| Oldland Montano | Oldland, Misty | Ole Ole |
| Oleander | Olenn, Johnny | Oli Max & D.J. Shapps |
| Oli.P | Olive | Olive Juice |
| Olive, Brian | Olivelawn | Oliver |
| Oliver Books calendars | Oliver Dawson Saxon | Oliver Naylor's Seven Aces |
| Oliver, David | Oliver, Frankie | Oliver, Graham |
| Oliver, King | Oliver, Sy | Oliveri, Nick |
| Olivia De Havilland | Olivia Tremor Control, The | Olivier, Laurence |
| Olivor, Jane | Ollie & Jerry | OLO Worms |
| Olsen, Angel | Olsen, George | Olsher, Lesley |
| Olson, Mark | Olsson, Kai | Olsson, Mats And His Orchestra |
| Olympia Dukakis | Olympic Bouzouki Group, The | Olympic Lifts |
| Olympic Runners | Olympic World | Olympics, The |
| Omar | Omar And The Howlers | Omarion |
| Omartian, Michael | Omartian, Michael And Stormie | OMC |
| Omega | Omega Amoeba | Omega Tribe |
| Omen | Omen III | Omerta |
| Omni Trio | Omsk Russian Ensemble, The | On Offs, The |
| On The One | On The Seventh Day | On The Speakers |
| On/Off | Once Again | Once Blue |
| Onda Del Futuro | One | One 2 Many |
| One Day As A Lion | One Dove | One God Universe |
| One Hand One Heart | One Hundred Ton And A Feather | One Hundred Words For Snow |
| One II One | One In A Million | One Lady Owner |
| One Minute Silence | One More Time | One Nation |
| One Night Only | One O'Clock Gang | One The Juggler |
| One Thousand Violins | One Three, The | One To One |
| One Trive | One True Voice | One, Act |
| One, Arkestra | One, As | One-Eyed Jacks |
| Oneida | Onelinedrawing | Oneness Of Juju |
| OneRepublic | Ones, The | OneTwo |
| Ong, Olivia | Onionhead | Only Child |
| Only If You Call Me Jonathan | Only Lonely | Only Ones |
| Ono, Kim | Ono, Seigen | Ono, Yoko |
| Onono, Ben | Onset, The | Onslaught |
| Onuora, Oku | Onward International | Onyeabor, William |
| Onyx | Onyx, The | Ooberman |
| Oomph | Oosterhuis, Trijntje | Oozay |
| Opa | Opal | Opal Butterfly |
| Opaz | OPE | Open Hand |
| Open In Obscurity | Open Mind, The | Open Road |
| Open Sky | Open, The | Operahouse |
| Operation Ivy | Operator Please | Operators, The |
| Opeth | OPM | OPM (Disco) |
| Oporto | Opossom | Oppenheimer |
| Opposition | Opsahl & Lindstedt | Optic Eye |
| Optimist Club | Optimum Wound Profile | Optimystic |
| Opus | Opus Dead | Opus III |
| Opus Int Music Ltd | Or-N-More | Ora |
| Ora, Rita | Orabge | Oral Exciters, The |
| Orange Alabaster Mushroom, The | Orange And Blue | Orange Bicycle, The |
| Orange Blossom Sound | Orange Can | Orange Deluxe |
| ORANGE GOBLIN | Orange Juice | Orange Lights, The |
| Orange Peel | Orange Power | Orange, Richard |
| Oranger | Orans | Orb |
| Orbidöig | Orbison, Roy | Orbit, William |
| Orbital | Orbo Equitum Solis | Orca |
| Orch. Of The Amsterdam Phil. | Orchestra Baobab | Orchestra Filarmonica Di Roma |
| Orchestra Folklore Di Romagna | Orchestra Luna | Orchestra Makassy |
| Orchestra Of St. James, The | Orchestra Of The Opera-Comique | Orchestra Tango Cafe |
| Orchestre De L'O.R.T.F. | Orchestre De La Suisse Romande | Orchestre De Monte Carlo |
| Orchestre Eddie Roger | Orchestre Jazira | Orchestre T.P.O.K. Jazz |
| Orchid | Orchids (60S), The | Orchids, The |
| Ordeal, DJ | Ordinary Boys, The | Ordinary Man |
| Oregon | Orellana, Raúl | Orff, Carl |
| Orford, Martin | Organ, The | Organisation |
| Organisms | Organization | Organized Konfusion |
| Organum | Orgazmo | Orgy |
| Orianthi | Orielle | Oriental Wind |
| Origin Unknown | Origin, The | Original Bedroom Rockers |
| Original Cast Recording | Original Concept | Original Dixieland Jazz Band |
| Original Mirrors | Original Sound Track, The | Original Soundtrack |
| Original Surfaris | Original Trinidad Steel Band | Original Tuxedo Jazz Band, The |
| Original, The | Originals, The | Orioles, Felders |
| Orioles, The | Orion (Elvis) | Orion (Ryan Adams) |
| Orion The Hunter | Orkest, Metropole | Orkestra |
| Orlando (60s) | Orlando (90s) | Orlando Johnson & Trance |
| Orlando Quartet | Orlando, Tony & Dawn | Orleans |
| Orlons, The | Orme, Le | Ormonde Folk, The |
| Ornadel, Cyril | Ornament | Ornamental |
| Orphan Egg | Orpheus | Orphic Soop |
| Orquesta De Antonio Bustamante | Orquesta Española De Baile | Orquestra Casino De Sevilla |
| Orquestra Sinfônica Brasileira | Orr, Benjamin | Orrall, Robert Ellis |
| Orrico, Stacie | ORS | Orson |
| Orson Family, The | Ortega, Jeannie | Ortiz, Cristina |
| Ortolani, Riz | Orton, Beth | Orwell, Paul |
| Ory, Kid | Ory,Kid And Allen, Red | Oryema, Geoffrey |
| Orzabal, Roland | Os Diagonais | OS Mutantes |
| Os Originais Do Samba | Osa, Sigbjørn Bernhoft | Osborne & Giles |
| Osborne Brothers, The | Osborne, Jeffrey | Osborne, Joan |
| Osborne, Mike | Osborne, Mike & Tracey, Stan | Osborne, Paul |
| Osborne, Tony | Osbourne, Johnny | Osbourne, Ozzy |
| Osby, Greg | Oscar | Oscar Peterson & Milt Jackson |
| Oscillation, The | Ose | OSH |
| Oshik Levy & Naftaly Alter | OSI | Osibisa |
| Osipov Academic Russian Folk O | Osiris | Oskar, Lee |
| Oslin, K.T. | Oslo Philharmonic Orchestra | Osmond Boys |
| Osmond, Donny | Osmond, Jimmy | Osmond, Marie |
| Osmonds, The | Osmosis | Ossian |
| Ossie & The Upsetters | Osterman Weekend, The | Ostrogoth |
| Osymyso | Otep | Other Half, The |
| Other Ones, The | Other People | Other Two, The |
| Othermothers, The | Others [1960S], The | Otherwise |
| Otis & The King Pins | Otis Johnny | Otis Williams And His Charms |
| Otis, Shuggie | Ottawan | Ottewell, Ben |
| Otway & Barrett | Otway John | Ou Est Le Swimming Pool |
| Oui 3 | Ouida & The Numbers | Ounsworth, Alec |
| Our American Cousins | Our Broken Garden | Our Daughters Wedding |
| Our Favourite Band | Our Future Feelings | Our Heaven |
| Our Kid | Our Lady Peace | Our Tribe |
| Ousset, Cécile | Out Of My Hair | Out Of The Blue |
| Out Of Your Mouth | Out With Mummy | Out, Papercut |
| Out-Phaze | Outcasts | Outcry Collective |
| Outer Limits, The | Outfield | Outhere Brothers, The |
| Outkast | Outlander | Outlandish |
| Outlaw Blues Band, The | Outlaws, The (UK) | Outlaws, The (US) |
| Outloud | Outnumbered, The | Outpatience, The |
| Outrage | Outrider | Outside |
| Outsiders (Punk), The | Outsiders, The | Outsiders, The |
| Outsiders, The | Outsiders, The (US) | Outskirts Of Infinity |
| Outskirts, The | Ova | Ovary Lodge |
| Overdraft, The | Overkill | Overlanders, The |
| Overload, Honcho | Overlord | Overlords, The |
| Overmono | Overstreet, Tommy | Overtones, The |
| Owen | Owen And Leon | Owen, Mark |
| Owen, Michael | Owen, Ray | Owen, Reg |
| Owen, Sid & Patty Palmer | Owens, Buck | Owens, Frank |
| Owens, Jack | Owens, Jamie | Owens, Jimmy |
| Owens, Robert | Owens, Tim 'Ripper' | Owens, Tony |
| Owl Service, The | Owls | Oxbow |
| Oxfam Glamour Models | Oxford Nights, The | Oxford, Vernon |
| Oxide Neutrino | Oxley, Louie | Oxley, Tony |
| OXO | Oxy And The Morons | Oxym |
| Oyster Band, The | Oysterband | Oysterhead |
| Oyuugi Wagamama Dan X PaRADEiS | OZ Magazine | Ozark Mountain Daredevils, The |
| Ozo | Ozomatli | Ozone |
| Ozone, Makoto | Ozric Tentacles | Ozzie Warlock And The Wizards |