- O'Chi Brown
- O-Town
- O-Zone
- O.C. Smith
- O.C.Smith
- O.R.G.A.N.
- Oakenfold
- Oas#s
- Oasis
- Oasis.
- Obernkirchen Children's Choir
- OBI Project
- Obie Trice
- Obituary
- Ocean Colour Scene
- Oceanic
- Oceanic With Siobhan Maher
- Oceanlab
- Oceansize
- Octave One
- Octopus
- Odd Future
- Odyssey
- Of Monsters & Men
- OFF
- Off-Shore
- Ofra Haza
- Oh Laura
- Oh Well
- Ohio Express
- OK Go
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- Ol' Dirty Bastard
- Olav Basoski
- Old Skool Orchestra
- Oleta Adams
- Olga
- OliMax And DJ Shapps
- Olive
- Oliver
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- Oliver Lieb Presents Smoked
- Olivia Newton-John
- Olivia Newton-John And Cliff Richard
- Olivia Newton-John And Electric Light Orchestra
- Ollie And Jerry
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- Omar
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- One 2 Many
- One Blood
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- One Minute Silence
- One Night Only
- One The Juggler
- One Tribe
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- One True Voice
- One Twelve
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- One World Project
- OneRepublic
- Oneworld
- Only Men Aloud
- Only Ones
- Onslaught
- Onyx
- Oo La La
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- Opeth
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- Opus
- Opus III
- Oran 'Juice' Jones
- Orange
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- Orange Lemon
- Orbital
- Orbital And Angelo Badalamenti
- Orchestra On The Half Shell
- Orchestral Manoeuvres In The Dark
- Ordinary Boys
- Origin
- Origin Unknown
- Original Broadway Cast
- Original Broadway Stage Cast
- Original Cast
- Original Cast Recording
- Original Concept
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- Original Soundtrack
- Original Studio Cast
- Original Television Soundtrack
- Orion
- Orion Too
- Oris Jay Presents Delsena
- Orlando Johnson And Trance
- Orlons
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- Osibisa
- Osmond Boys
- OT Quartet
- Other Tribe
- Other Two
- Otis Redding
- Otis Redding & Aretha Franklin
- Otis Redding & Carla Thomas
- Otis Redding And Carla Thomas
- OTT
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- Otto Knows
- Oui 3
- Our Daughter's Wedding
- Our House
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- Our Lady Peace
- Our Tribe
- Our Tribe With Frankie Pharoah And Kristine W
- Out Of My Hair
- Out Of Office
- Outfield
- Outkast
- Outlander
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- Outrage
- Outsidaz
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- Outwork
- Ovacast & Becky Measures
- Overlanders
- Overlord X
- Overtones
- Overweight Pooch And Ce Ce Peniston
- Owen Paul
- Owl City
- Oxide And Neutrino
- Oxygen
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- Ozzy And Kelly Osbourne
- Ozzy Osbourne
- Ozzy Osbourne's Blizzard Of Ozz
- The Orb