So, do you buy each song separately digitally or physically? Also, after buying, how do you move it to your setup? For physical copies (CDs or Vinyls), do you rip and convert them to .flac or .mp3? For digital, do you remove the DRM?
As far as getting music to and from my setup, I'm usually pretty old fashioned. I have an external hard drive that I use for backup, and a thumb drive or two. Further, I have Owncloud set up on a Raspberry Pi, which is nice for moving a few files, but wouldn't be suitable for moving files of any real volume. Obviously, anyone could build a more mature and robust network drive if they liked, but this setup is more than suitable for my needs.