If you can pull yourself out of Azeroth for a few minutes, here's some interesting reading for you. World of Warcraft: Rise of the Horde is a novel by Christie Golden. It's the prologue of the Burning Crusade and features the origins of the Draenei and the corruption of the orcs.

Cast includes Durotan (Thrall's father), Ner'zhul, Drek'Thar, Gul'dan, Doomhammer, Hellscream, Kil'jaeden, Velen and many others. The story is alternately told from Durotan's, Thrall's, and a third person point of view. The book also features several familiar places like Terokkar Forest, Hellfire Peninsula, and Shattrah.

The author, Christie Golden (who also wrote Warcraft: Lord of the Clans) is also a WoW fan and apparently plays on an RP server. Reportedly, some events in the book were incorporated to the expansion as quests, Blizzard and the author collaborated for those additions.

Histories of Grom Hellscream and Orgrim Doomhammer are included in the book, so those who enjoy WoW's lore can discover how/why Grom drank Mannoroth's blood and bound the orc race to the Burning Legion. Well enough babbling, you can go and check out the book yourself.