Old iTunes

"iTunes" is the name we all use when referring to several different services and that then leads to the confusion. Separate the idea of an iTunes account and an iTunes Library:

• • iTunes Library: The music from your CDs, digital mp3s from Amazon, Bandcamp, or other sources is stored on your computer and listed and playable in your iTunes Library ("in iTunes")
  • iTunes Account: an iTunes account (accessible through "iTunes") is the account you specifically set up in the iTunes Store, so you can buy digital copies of music from Apple

Two different things. You do not and have never needed an iTunes Account in order to use iTunes with your CD music or non-Apple purchases.

Apple do not save or keep your music, unless using the iCloud, which is an ongoing subscription service. Since you didn't mention that, I have assumed you don't use it.

Any music that you had in your iTunes Library that came from your CDs or other non-Apple sources would have been stored on your computer - not the iTunes Store and not "in your account". You don't need iTunes to access that music, but you do need the music files themselves, so the only way to access those files would be on the computer that the music was added to (with or without iTunes), or from a backup made by you.

Failing that:

• for your CDs, do you still have the CDs that you originally used? If so, use them for your current music library
• for music purchased from other sources, go to your account with that source and see if you can download the music again. Amazon and Beatport purchases will still be available in your account (with that store) unless there are copyright issues.