Give it a while to load... there are a lot of .mp3 files...

Watch your volume! ... Especially if you're wearing headphones. Some of these songs are loud, some of them are soft. Just a fair warning so that hopefully nobody blows their eardrums out.

So this is a list of all the songs used in https://pacthesis.deviantart.com/gallery/30972861.
Keep in mind that all of these but "Astronauts" are the full, unedited version so they may sound a little different than what you heard in the game.

When you click on the download button, your computer should automatically download the file and it'll show up in the place where ever you set your downloads to go to. But for "Astronauts" there's a "download" button on the page that pops up when you try to download them.
If your internet's being a butt, you can look up the titles and download directly from http://incompetech.com/m/c/royalty-free/, excluding "Astronauts".