So in Part 1, the music files are just sitting in a folder in WAV format. Interestingly enough, there is a file that lists all of the music files and there are quite a few in the list that aren't actually in the music folder. Here's that list:
http://pastebin.com/tuBspWz9
In Part 2, I was able to extract all of the WAV files. Several of them were duplicates of the ones from Part 1 while some were ones I hadn't heard yet. According to the Steam page, there were 4 new songs added in Part 2. I was able to open the unknown WAV files in a hex editor and find the track names for all but six. I would assume 4 of them are for sure the new songs in Part 2, while the other two may be ambient tracks they don't categorize as songs. I was also not able to find track names for "Train Station" and "Hartman's Speech" in either of those six files, so I'm not sure if the other two tracks are these or not.
Link:
https://mega.nz/#!4olwmZRR!icuaoy38LzrfTgO-a0FcpUI64C9iyzkbpdFeLxbM9I0