Recently I lost my iTunes folder containing all the music.
I had a fault in my iMac and I was forced to restore it from the Time Machine backup.
Everything, except the about 200 GB of music (and 1 ringtone) could be restored, the music unfortunately could not be found in any of the backups.
Most of the music I love was ripped from CDs and could be restored by ripping them again (this time in loss less formats, ALAC).
I had also some online purchases from Linn, Analektta, HDTracks and iTunes.
The Linn and Analecta sites allow to download again the purchased albums.
iTunes was kind enough to reactivate all my downloads upon receiving an email from me.
Unfortunately HDtracks (highly recommended by Stereophile and probably the biggest library of High Definition tracks and albums) has so far refused to allow me to download again the about 30 albums that I paid for.
I do not understand why considering that I have all receipts, the tracks have no DRM and their online records show all my purchases. (I could recover about 50% from old hard disks and copies I found in my restored folders but the rest is definitely gone)
Also to be fair HDtracks allowed me to get back my last 2 purchases and claims that they are unable to enable me to download the rest for "technical reasons"
From now on I am going to purchase online only from sites that allow to download the music again if needed and recommend to the fellow audiophiles that read this to do the same and to give priority to "hard copies" (i.e. CDs, SACDs or Vynil)
If other readers had similar experiences I will appreciate if you share them through this forum