Taming Eastern Kingdoms

Going through the quest line which starts with Audrey Burnhep, one will encounter the following trainers in chronological order:

Julia Stevens, for the quest Julia, The Pet Tamer is located in Elwynn Forest. Coords: 41, 83.
Pets (lvl 2, Common):
Beast (Fangs, Slither) - use Mechanical

Old MacDonald, for the quest Old MacDonald is located in Westfall. Coords: 60, 18
Pets (lvl 3, Common):
Flying (Clucks) - use Magic
Mechanical (Foe Reaper 800) - use Elemental
Critter (Teensy) - use Beast

Lindsay, for the quest Lindsay is located in Redridge Mountains. Coords: 33, 52
Pets (lvl 5, Common):
Critter (Dipsy, Flipsy, Flufftail) - use Beast

Eric Davidson, for the quest Eric Davidson is located in Duskwood. Coords: 20, 44
Pets (lvl 7, Common):
Beast (Blackfang, Darkwidow, Webwinder) - use Mechanical

Steven Lisbane, for the quest Steven Lisbane is located in Northern Stranglethorn. Coords: 46, 40
Pets (lvl 9, Common):
Magic (Emeralda) - use Dragonkin
Beast (Moonstalker, Nanners) - use Mechanical

Bill Buckler, for the quest Bill Buckler is located in The Cape of Stranglethorn. Coords: 51, 73
Pets (lvl 11, Uncommon):
Humanoid (Burgle) - use Undead
Flying (Eyegouger, Young Beaky) - use Magic

After defeating Bill Buckler, you get the quest A Tamer's Homecoming. The completion of this unlocks both Battle Pet Tamers: Eastern Kingdoms and Battle Pet Tamers: Kalimdor.

As this is the page for Taming Eastern Kingdoms, I will present the tamers met throughout Battle Pet Tamers: Eastern Kingdoms.

David Kosse is located in The Hinterlands. Coords: 62, 54
Pets (lvl 13, Uncommon):
Beast (Corpsefeeder) - use Mechanical
Magic (Plop) - use Dragonkin
Critter (Subject 142) - use Beast

Deiza Plaguehorn is located in Eastern Plaguelands. Coords: 67, 52
Pets (lvl 14, Uncommon):
Beast (Bleakspinner, Carrion) - use Mechanical
Undead (Plaguebringer) - use Critter

Kortas Darkhammer is located in Searing Gorge. Coords: 35, 27
Pets (lvl 15, Uncommon):
Dragonkin (Garnestrasz, Obsidion, Veridia) - use Humanoid

Everessa is located in Swamp of Sorrows. Coords: 76, 41
Pets (lvl 16, Uncommon):
Beast (Anklor) - use Mechanical
Aquatic (Croaker) - use Flying
Flying (Dampwing) - use Magic

Durin Darkhammer is located in Burning Steppes. Coords: 25, 47
Pets (lvl 17, Uncommon):
Flying (Comet) - use Magic
Critter (Ignious) - use Beast
Elemental (Moltar) - use Aquatic

The follow-up from Battle Pet Tamers: Eastern Kingdoms is Grand Master Lydia Accoste,
where one has to defeat Lydia Accoste whom is located in Deadwind Pass. Coords: 40, 76
Pets (lvl 19 - Uncommon Elite):
Undead (Bishibosh, Nightstalker) - use Critter
Elemental (Jack) - use Aquatic

Congrats on your achievement!

Oh My LORD. It would be REALLY nice if it was noted SOMEWHERE in the game that the Eastern Kingdoms pet tamer battles are for Ally toons ONLY!

Don't USE -----------ENEMY-----------USE
Magic------------------Aquatic------------Flying
Flying----------------- Beast -------------Mechanical
Humanoid-------------Critter-------------Beast
Undead----------------Dragonkin--------Humanoid
Critter------------------Elemental---------Aquatic
Dragonkin-------------Flying-------------Magic
Beast-------------------Humanoid--------Undead
Mechanical------------Magic-------------Dragonkin
Elemental -------------Mechanical------Elemental
Aquatic-----------------Undead-----------Critter

Guide: To help you pick the correct Battlepet depending on what your opponent uses.

/enjoy