"O" Ringtones
- O.A.R.
- O.S.I.
- O'Ryan
- Oasis
- Obiat
- Obie Trice
- Obituary
- OBK
- Obstinacy
- Occult
- Ocean Colour Scene
- October 31
- October File
- October Project
- Odd Project
- Of Montreal
- Oforia
- Ofra Haza
- Oh No
- Ohgr
- Oi Va Voi
- Oidoxie
- Oil
- Oingo Boingo
- OK Go
- Oka Road
- Okkervil River
- Oktober
- Ol' Dirty Bastard
- OLD
- Old Crow Medicine Show
- Old Dead Tree
- Old Man Gloom
- Old Man's Child
- Old School 101
- Oldominion
- Oleta Adams
- Olive
- Oliver Jones
- Oliver Knussen
- Oliver Shanti
- Oliver Wallace
- Olivia Newton-John
- Olmarin Unioni
- Ololiuqui
- Omar
- Omar a Lopez Rodriguez
- Omar and The Howlers
- Omar Pedrini
- Omarion
- OMD
- Omega
- On A Solid Rock
- On Golden Blonde
- On Thorns I Lay
- Ondskapt
- One Be Lo
- One Block Radius
- One Day As A Lion
- One Last Hope
- One Life Crew
- One Man Army
- One Minute Silence
- One On One
- One Shot
- Onelinedrawing
- OneRepublic
- Onesidezero
- Oneyed Jack
- Onslaught
- Onyx
- Oomph
- Opera IX
- Opeth
- Ophidian
- Ophthalamia
- Opium
- OPM
- Oppressor
- Optimum Wound Profile
- Opus
- Opus III
- Oran Juice Jones
- Orange 9mm
- Orange Goblin
- Orange Juice
- Orange Range
- Orange Sector
- Orbital
- Ordinary Peoples
- Ordo Draconis
- Ordo Equilibrio
- Oreiro
- Orgy
- Orishas
- Ork
- Ornette Coleman
- Orphanage
- Orphaned Land
- Orplid
- Orson
- Osamu Kitajima
- Oscar Peterson
- OTEP
- Otis Redding
- Otis Spann
- Ottawan
- Ottmar Liebert
- Otyg
- Our Lady Peace
- Our Turn
- Out
- Out Of Reach
- Out To Win
- Outcast
- OutKast
- Outlandish
- Outlawz
- Ouzo
- Over The Rhine
- Overcome
- Overdrive
- Overkill
- Overseer
- Oxford Circle
- Oxygiene 23
- Oystein Sevag
- O-Zone
- Ozric Tentacles
- Ozzy Osbourne
