Ohbijou
Ojiji
OK Cobra
Okazaki Fragments
Okoumé
Ol' Time Moonshine
Old Chicago Blues Band
Old World Vulture
Olenka and the Autumn Lovers
Oliver Black
George Olliver
Olympic Symphonium
Omega Crom
One Bad Son
One Blood
One More Girl
Joey O'Neil
Mike O'Neill
Open Eyes Elysia
Operation Winter Mist
Opus-5
Opusculus
The Orchard
L' Orchestre Sympathique
Orchidectomy
Orchid’s Curse
Maren Ord
Gary O'
Obduracy
Obey the Brave
Obscene Crisis
Obscene Eulogy
Obscuris Romancia
Obsek
Obsydian
Obvurt
Obyrne
Roberto Occhipinti
Occult Burial
Ocean Machine
Oceans Will Rise
Audrey Ochoa
October Sky
Octoberman
Octobre
Ocular Trauma
Odin’s Law
Odium
Of Burning Empires
Of Concepts and Kings
Of Doomed Morale
Of Hatred Spawn
Of Sound Mind
Of Temples
Off The Mark
Offenbach
Nivek Ogre
Maggie Blue O'Hara
Mary Margaret O'Hara
Oh No Forest Fires
Oh Susanna
Organ
Original Sloth Band
Achilla Orru
Lindi Ortega
Oryzhein
Simone Osborne
Marg Osburne
Walter Ostanek
Ostie
John Oswald
Osyron
Ouba
Karim Ouellet
Ought
Marie-Josee Ouimet
Our Lady of Bloodshed
Our Lady Peace
Our Mercury
Our War
Ours to Destroy
Out of the Blue
Out of Your Mouth
Ov Hollowness
Ovif
Ox