The Elder Days
Tolkien’s earliest and most worked upon writings concerned ‘The Elder Days’, starting with the creation of the Ainu and then the universe and leading up to the Third Age. From an audio perspective, the titles that we have at present are:
Beren and Lúthien
The Children of Húrin
The Fall of Gondolin
The Fall of Númenor
The Silmarillion
Unfinished Tales

Dates of January 1st indicate that the exact day of the year is not known.
Unfinished Tales: Norman Barrs
Library of Congress produced unabridged English reading
Silmarillion: Martin Shaw
HarperCollins produced abridged English reading
Unfinished Tales: Erin Jones
Library of Congress produced unabridged English reading
Children of Hurin: Christopher Lee
HarperCollins produced unabridged English reading
Children of Hurin: Gert Heidenreich
Die Kinder Húrins
Audio Publisher produced unabridged German reading
Silmarillion: LP Association
Le Silmarillion
Independent unabridged French reading
Fall of Gondolin: Timothy & Samuel West
HarperCollins produced unabridged English reading
Beren and Lúthien: Timothy & Samuel West
HarperCollins produced unabridged English reading
Children of Hurin: Thierry Janssen
Les Enfants de Húrin
Christian Bourgois produced unabridged French reading
Unfinished Tales: Samuel & Timothy West
HarperCollins produced unabridged English reading
Silmarillion: Thierry Janssen
Le Silmarillion
Audiolib produced unabridged French reading
Unfinished Tales: Heidenreich & Niesner
Nachrichten aus Mittelerde
Der Hörverlag produced unabridged German reading
Silmarillion: Toni Kamula
WSOY produced unabridged Finnish reading
Unfinished Tales: Toni Kamula
Keskeneräisten tarujen kirja
WSOY produced unabridged Finnish reading
Children of Hurin: Toni Kamula
Húrinin lasten tarina
WSOY produced unabridged Finnish reading
Silmarillion: Andy Serkis
HarperCollins produced unabridged English reading
Beren and Lúthien: Gert Heidenreich, Timmo Niesner
Beren und Lúthien
Der Hörverlag produced unabridged German reading
Beren and Lúthien: Locus
Beren et Lúthien
Independently produced unabridged French produced
The Fall of Gondolin: Locus
La Chute de Gondolin
Independently produced unabridged French produced
Unfinished Tales: Locus
Contes et Légendes Inachevés
Independently produced unabridged French produced
Fall of Númenor: Brian Sibley & Samuel West
HarperCollins produced unabridged English reading
Unfinished Tales: Thierry Janssen
Contes et Légendes Inachevés
Audiolib produced unabridged French reading
Children of Hurin: Tomáš Juřička
Húrinovy děti
Tympanum produced unabridged Czech reading
Fall of Númenor: Gert Heidenreich, Timmo Niesner, Johannes Steck
Der Untergang von Númenor
Der Hörverlag produced unabridged German reading
Silmarillion: Luis Posada
El Silmarillion
Planet Audio produced unabridged Spanish (Castilian) reading
Children of Hurin: Luis Posada
Los Hijos de Húrin
Planet Audio produced unabridged Spanish (Castilian) reading
Beren and Lúthien: Thierry Janssen
Beren et Lúthien
Audiolib produced unabridged French reading
Fall of Númenor: Tomi Kamula
Númenorin Tuho
WSOY produced unabridged Finnish reading
Silmarillion: Slušalište
Independent unabridged Bosnian reading
Fall of Gondolin: Thierry Janssen
La Chute de Gondolin
Audiolib produced unabridged French reading
Children of Hurin: Torben Sekov
Húrins Børn
Gyldendalske Boghandel produced unabridged Danish reading
Unfinished Tales: Torben Sekov
Efterladte Historier
Gyldendalske Boghandel produced unabridged Danish reading
Fall of Gondolin: Aleš Procházka
Pád Gondolinu
Tympanum produced unabridged Czech reading
Silmarillion: Torben Sekov
Gyldendalske Boghandel produced unabridged Danish reading
Beren and Lúthien: Jordi Boixaderas
Beren y Lúthien
Planet Audio produced unabridged Spanish (Castilian) reading
Fall of Gondolin: Jordi Boixaderas
La Caída de Gondolin
Planet Audio produced unabridged Spanish (Castilian) reading
Fall of Gondolin: Gert Heidenreich, Timmo Niesner
Der Fall von Gondolin
Der Hörverlag produced unabridged German reading