Librams are ancient keepsakes that are left of the Highborne legacy. Those codex are filled with indecipherable and skittering runes that can only be read by very few lore masters in the world. At this time there are only two such known - Mathredis Firestar, a recluse and crankly elf that resides in the Burning Steppes, and Lorekeeper Lydros from the secret archives of Shen'dralar in Dire Maul.
Librams can be turned in to one of those NPCs (each one only accept some librams), along with some other ingredients for an Arcanum, a gem that allows you to apply an enchant to a Head or Leg item. Only one libram of each type can be carried at a time, though the quests can be repeated any number of times. Before turning in Librams to Lorekeeper Lydros in Dire Maul, you have to complete the quest Elven Legends.
Lesser Arcanum
These can be handed in to Mathredis Firestar. Note that these quests do not generate experience, reputation or achievement gains. Nor can the resulting arcanum be applied to any but your own, Level 50+, head or leg item (see patch notes). However, a level 50-60ish character can buy the libram and any Blasted Lands items from the Auction House, and should be capable of running Blackrock Depths and Felwood for the other items.
Each turn-in requires a libram, a 
[Black Diamond], 30g and a few quest items:
[Libram of Tenacity] - 125 armor
[Crystal Ward] x4 (needs 10 Green & Red crystals; West pylon, Un'Guro crater)- [Eye of Kajal] (sometimes found inside the Dark Coffer inside Blackrock Depths).
- [Libram of Resilience] - 20 fire resistance
- [Crystal Spire] x4 (10 Blue & Yellow; East)
- [Burning Essence] (sometimes found inside the Dark Coffer inside Blackrock Depths).
- [Libram of Constitution] - 100 health points
- [Lung Juice Cocktail] (Blasted Lands; [Blasted Boar Lung] x3, [Scorpok Pincer] x2, [Basilisk Brain] x1)
- [Night Dragon's Breath] x4 (use 3 [Cenarion Plant Salve] on Corrupted Night Dragon in Felwood)
- [Libram of Voracity] - 8 Agility, Intellect, Spirit, Strength or Stamina
- [Crystal Force] x4 (10 green & blue; East Pylon)
- [Whipper Root Tuber] x4
Arcanum
These can be handed in to Lorekeeper Lydros in Dire Maul library. Other than a few quests in the area, turn-ins of these Librams are the only way to generate reputation with the Shen'dralar.
Each turn in requires a libram, a quest item, a 
[Pristine Black Diamond] and a few Large Brilliant Shards
See also
- See also: Augments for further details on the enchants provided.
Patch Notes
As of patch 3.1, Lesser Arcanum can ONLY be applied to your own head or leg item. Applying them causes the item to become soul bound (tested on Commander's Helm of Defense) "Enchanting this item will bind it to you". You can no longer apply them through a trade window (tested) "Can only be applied to your own items". They require Level 50.