| Artist | Album | Record Label | Released | Added To List | |
| O.V.N.I. | Good For You | Alfa Matrix | 2005 | 11/23/2005 | Request |
| Obscenity Trial | That Night | Major Records | 2008 | 10/26/2014 | Request |
| Obscure Descension | Obscure Descension | Atrocity Records | 2009 | 10/18/2009 | Request |
| Observe & Control | Utopia | Archetype Multimedia | 2005 | 1/1/2005 | Request |
| Obszon Geschopf | Son of Evil | BLC Productions | 2004 | 1/1/2005 | Request |
| ohGr | Welt | Spitfire Records | 2001 | 1/1/2005 | Request |
| ohGr | Undeveloped | Metropolis Records | 2011 | 6/26/2011 | Request |
| Ohm | Ohm | Artoffact Records | 2013 | 8/10/2014 | Request |
| Oneroid Psychosis | Stillbirth | Cop Int'l | 2003 | 1/1/2005 | Request |
| Oomph! | Ice Coffin | Modern Music Recors | 1995 | 1/1/2005 | Request |
| Opium | Too Many Miles Between Us | A Different Drum | 2004 | 1/1/2005 | Request |
| Orange Sector | Fur Immer Kalt View Stahl | Infacted Recordings | 2006 | 8/15/2006 | Request |
| Orange Sector | Mindfuck | Machineries Of Joy | April 20, 2009 | 9/5/2009 | Request |
| Orange Sector | Krieg & Frieden | Metropolis Records | July 13, 2010 | 9/21/2010 | Request |
| oRdnance | Ordnance | (None) | 2011 | 8/7/2011 | Request |
| Orgy | Vapor Transmission | Elementree Records | 2000 | 1/1/2005 | Request |
| Orphyx | Circuitbreaking | Hymen Records | 2004 | 1/1/2005 | Request |
| Out Out | 1989-1999: Hasten The Burning | Radio Valkyrie Records | 2005 | 1/1/2005 | Request |