Organ Trail

Link: http://bencrossbones.bandcamp.com/album/organ-trail-directors-cut-original-soundtrack 

A great mix of desperation fight-for-survival, and hollow emptiness, this album captures the excitement and loneliness of a zombie outbreak rather well. Listening to it from start to end is an unearthing experience, giving you a rush of adrenaline in places before taking it all away and leaving you with nothing but your thoughts.