I cannot remember any written piece of elfin history ...
... the Coneheads had their hive mind and the Scroll of Colors
... the Gliders had Aurek (Egg) and his seven-layered Great Egg
... the Sunfolk have her Mother of Memory
... the Wolfriders have storytellers and dreamberries
... the Go-Backs? I only remember that they count ... possibly storytellers as well
... the Wavedancers - no idea
What I remember is the mentioning of a Troll using sort of a written list about supplies or such stuff. Again I remember neither the thread where this was discussed not the source of the "Troll list" (possibly somewhere in the Wild Hunt storyline). We need Trollbabe ...
The conclusion was that a written language might be rather developed by Trolls then by Elves.
Of course the Coneheads can still have had a written language that had survived from their earlier times. Hardly used, but still understandable - not quite dead so far.