Step one: Buy gear off the AH.
Step two: Enchant the gear.
Step three: Run an instance, watch upgrades rain down upon you.
Unbreakable Guardian -> Gavel of Peroth'arn
Drape of Inimitable Fate -> Cloak of the Royal Protector
Witch-Hunter's Harvester -> Pit Lord's Destroyer
That doesn't count the chest I'd bought off the AH last winter and also upgraded, but maybe it should, since in all technicality, it was an AH item that was replaced after only a few runs. There were also ret shoulders and various healing items, which almost made me consider trying holy, until I remembered that healing is the hardest role in the game.
So sadly, I am no longer wielding a scythe. And my reforging is all wrong now. But I can finally get into LFR! Should I bother to read up on any fights?