There are at least two bands with this name:
These are photos from concerts where Unearth played, so they may be of other bands that played the concert as well.
Ozzfest 2004 Sep 2, 2004 Tampa, Florida, United States Uploaded by Bri Kel
Ozzfest 2004 Aug 28, 2004 Burgettstown, Pennsylvania, United States Uploaded by Basura Boy
Lamb of God / Atreyu / Every Time I Die / Unearth Aug 15, 2004 Minneapolis, Minnesota, United States Uploaded by Primus913
Ozzfest Aug 10, 2004 Bonner Springs, Kansas, United States Uploaded by Kansas City Concert Fiendz
Ozzfest 2004 Aug 5, 2004 Dallas, Texas, United States Uploaded by Alex Comeaux
Ozzfest 2004 Aug 5, 2004 Dallas, Texas, United States Uploaded by David Mills
Ozzfest 2004 Aug 5, 2004 Dallas, Texas, United States Uploaded by Matt C
Ozzfest 2004 Aug 3, 2004 Albuquerque, New Mexico, United States Uploaded by Djmabq
Sick of It All / 7 Seconds / Slapshot / The Bones / Unearth / Walls of Jericho Jul 30, 2004 Wiesbaden, Hesse, Germany Uploaded by Manuel Kainz
Ozzfest 2004 Jul 29, 2004 Mountain View, California, United States Uploaded by Killerwolf13