The Consortium Quartermaster Karaaz can be found in Netherstorm at Stormspire, near the elevator.  To gain reputation with the Consortium you must complete quests in Terokkar Forest by the northern dungeon wing of Auchindoun.  Other quests can be found in Nagrand at Aeris Landing, Shattrath City, and Netherstorm at Area 52, Eco-dome Midrealm, Echo-dome Sutheron, Protectorate Watch Post and Echo-dome Fairfield.  A great way to increase reputation with the Consortium is to play many runs killing mobs in Auchindoun: Mana Tombs dungeon-wing located at the Bone Wastes in Terokkar Forest.

You should worry to increase reputation with the Consortium if you are a Jewelcrafter, Enchanter, Tailor or Leatherworker. There is only one enchant formula at friendly, and a tailor recipe at honored.  The gear appeals mostly to rogues, hunters and cloth-casters.