Legions of Steel Soundtrack:

Steam downloads game soundtracks to a separate folder in your game's Steamapps directory.
You can right-click on a game in your Steam Library, select Properties>Local Files and click Browse Local Files to access that game's directory.

The soundtrack itself consists of 3 tracks by Yogan Le Fouler-Barthela and Wang Qian:

Stellar Coldness Quagmire 05:41
Edge of Darkness 03:44
Earth Dogs Die Hard 02:31