Start in the beginning graveyard area of Western Plaguelands. Have the warlock gather and DoT 4-8 undead mobs and bring them to the paladin. The Paladin should use the Holy Wrath getting all agro off of the Warlock then drop the Consecration AoE to maintain agro. (Using the Retribution aura helps do a bit more damage but make sure your other party members are out of harms way if they do not have the same level of AC).

During AoE usage and Hammer of Justice usage the Warlock should DoT up missed mobs and start dropping Hellfire and Rain of Fire.

All the while, the healing person should just be healing the Paladin and casting a renew or rejuvenation on the Warlock helping keep them alive during their AoE disbursement.

After the 4-8 mobs die, take a rest and eat up and get ready for the next run. It may be even better with 1 more Paladin to double up on the undead fighting abilities. Also by the time you are done with the first mob set your paladins Holy Wrath spell with be cooled down again. Get Powerleveling here.

Don’t forget to gather the scourge stones. To maximize your gathering you can bring with you lower level help that may not have the insignia yet. The more scourge stones you get the better the rep with AD as you turn them in.

Rinse Lather and repeat. Before you know it you will go from Neutral to Friendly and be able to then buy Mana Biscuits and continue the rep grind for You can do this all day long with very low chance of being gangked by passing horde.