If you don't know where the soundtrack is, look at the guide.
DLC
https://store.steampowered.com/app/1149110/
https://store.steampowered.com/app/1103260/
https://store.steampowered.com/app/1221870/
Developer announcements, patch notes and gaming coverage from across the GaugeDB catalogue.
Source: Steam Community (opens in a new tab)
If you don't know where the soundtrack is, look at the guide.
DLC
https://store.steampowered.com/app/1149110/
https://store.steampowered.com/app/1103260/
https://store.steampowered.com/app/1221870/