
| O | 35 | |
| Obscenity: Demo-Niac (1999) | ||
| Obscura: Cosmogenesis (209) | ||
| Occult (Hol): Of Flesh And Blood (1999) | ||
| Occult (Hol): Elegy For The Weak (2004) | ||
| Occult (Hol): Prepare To Meet Thy Doom (1994) | N/A | |
| Oceano: Depths (Limited Edition) (2009) | ||
| Octavia Sperati: Winter Enclosure (2005) | N/A | |
| Octinomos: On The Demiurge (1995) (Rare artwork needs to be replaced) | N/A | |
| Old Man's Child: Vermin (2005) | ||
| Old Man's Child: Slaves Of The World (2009) | ||
| Opeth: Deliverance (2002) | N/A | |
| Opeth: Ghost Reveries (2005) | N/A | |
| Opeth: Mellotron Heart (2008) | N/A | |
| Opeth: Watershed (2008) | N/A | |
| Organic Infest: The Way To Temptation (2003) | N/A | |
| Orgy: Candyass (1998) | ||
| Orgy: Punk Statik Paranoia (2004) | ||
| Orgy: Vapor Transmission (2000) | ||
| Origin (US): A Coming Into Existence (Demo) (1998) (Autographed) | N/A | |
| Origin (US): Antithesis (2008) | ||
| Origin (US): Echoes Of Decimation (2005) | ||
| Origin (US): Informis Infinitas Inhumanitas (2002) | ||
| Orphanage: Driven (2004) | N/A | |
| Orphanage: Inside (2000) | N/A | |
| Orphaned Land: Mabool - The Story Of Three Sons Of Seven (Limited Bonus Disc Edition) (2004) | ||
| OSI: Office Of Strategic Influence (2003) | N/A | |
| Overkill (US): Bloodletting (2000) | N/A | |
| Overkill (US): From The Underground And Below (1997) | N/A | |
| Overkill (US): Horrorscope (1991) | N/A | |
| Overkill (US): I Hear Black (1993) | ||
| Overkill (US): Immortalis (2007) | ||
| Overkill (US): Ironbound (2010) | ||
| Overkill (US): Killbox 13 (2003) | ||
| Overkill (US): ReliXIV (2005) | ||
| Overlord's Perpetual: Overlord's Perpetual (2005) (Promotional version) | N/A | |
| Ozzy Osbourne: Down To Earth (2001) | ||