- Beth Orton
- Bobby Orlando
- Carl Orff (Карл Орфф)
- Danny O'Keefe
- DJ Orbit
- Eddie Ojeda
- Evan Olson
- Helen O'Hara
- Jacques Offenbach
- Johnny Otis
- Mark Olson & Gary Louris
- Mark Owen
- Martin Orford
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- Natalia Oreiro
- O Peso
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- Oda
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- OFF
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- One
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- One In A Million
- One Less Reason
- One Man Army and the Undead Quartet
- One Minute Silence
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- Onesidezero
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- Onyx
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- Orbital
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- Ray Owen's Moon
- Rob Orlemans & Half Past Midnight
- Roland Orzabal
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- The Odd Numbers
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- The Outlaw Blues Band
- The Outlaws
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- Tim Ripper Owens
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