I was told years ago that whenever a new hidden service is created it is added to a list, so there is a record of every hidden service ever created. I believe the list is somewhere on the Tor project website.
If this is true could somebody please provide a link? I need this for my research.
There is no record of onion addresses kept anywhere in Tor network. Tor hidden services upload their descriptor on a Tor hidden service directory (HSDir) in a distributed hash table. The descriptor contains the information about introduction points and public keys through which a hidden service can be contacted.
To request descriptor from HSDir, one should already have pre-knowledge of its onion address which is learned out of band such as through email, advertisement or if the hidden service owner is telling you in person. The descriptor itself does not contain the onion address of the hidden service.
But there were some attempts in the past to collect the onion addresses of hidden services by using a technique called harvesting onion addresses through which a malicious HSDir learns onion addresses from the public key present in descriptors. With v3 onions, the descriptors are now encrypted which can be only decrypted by the client who knows the onion address.
