O   | O Fracas | O Level |
| O Suilleabhain, Micheal | O Toole, Peter | O Yuki Conjugate |
| 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 | Oattes Van Schaik |
| Obelisk | 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 Blood | 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 | Onyeka The Torch | 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 Caretas | 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, Ed & Ben | Otis, Shuggie | Ottawan |
| Ottewell, Ben | Otway & Barrett | Otway John |
| Ou Est Le Swimming Pool | Ouch | 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 Lunar Activities | 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 | Outer Limits, The | Outfield |
| Outhere Brothers, The | Outkast | Outlander |
| Outlandish | Outlaw Blues Band, The | Outlaws, The (UK) |
| Outlaws, The (US) | Outline, The | 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 |