Battle Pet Tamers: Eastern Kingdoms

Here is my Quicklist Guide to the second tier of Pet Trainer Quests. This is a quick reference to see what type of pets you will need to defeat the trainers easily. On Trainers who have the same type of pet for all 3 pets in their party, I would recommend you bring at least two pets that are the opposite type (i.e. bring three appropriate leveled Mechanical types to fight three trainer Beasts). Don't rely on fighting all three of their pets with just one of yours, despite the fact that they will have stronger attacks and defeat them quicker.

Battle Pet Tamers: Eastern Kingdoms

To defeat these trainers with maximum efficiency, you will need pets of the following type:
Beast, Mechanical, Dragonkin, Critter, Humanoid, Flying, Magic, Aquatic

David Kosse - The Hinterlands – Level 13
Quickteam List – Level 13 Beast, Mechancial, Dragonkin
Pet 1: Subject 142 – Critter – Use Beast
Pet 2: Corpsefeeder – Beast – Use Mechanical
Pet 3: Plop – Magic – Use Dragonkin

Deiza Plaguehorn – Easter Plaguelands – Level 14
Quickteam List – Level 14 Mechanical, Critter
Pet 1: Carrion – Beast – Use Mechanical
Pet 2: Bleakspinner – Beast - Use Mechanical
Pet 3: Plaguebringer – Undead – Use Critter

Kortas Darkhammer – Searing Gorge – Level 15
Quickteam List – Level 15 Humanoid
Pet 1: Garnestrasz – Dragonkin – Use Humanoid
Pet 2: Veridia – Dragonkin – Use Humanoid
Pet 3: Obsidion – Dragonkin – Use Humanoid

Everessa – Swamp of Sorrows – Level 16
Quickteam List – Level 16 Flying, Magic, Mechanical
Pet 1: Croaker – Aquatic – Use Flying
Pet 2: Dampwing – Flying – Use Magic
Pet 3: Anklor – Beast – Use Mechanical

Durin Darkhammer- Burning Steppes – Level 17
Quickteam List – Level 17 Magic, Beast, Aquatic
Pet 1: Comet – Flying – Use Magic
Pet 2: Ignious – Critter – Use Beast
Pet 3: Moltar – Elemental – Use Aquatic

*Author's Note: In writing this guide, I used various references from wowhead and warcraftpets.com. I did not write this guide as I was doing each trainer. Some information might be wrong. Please feel free to comment and I will change it as needed.

David Kosse - - Hinterlands
(Further east than the quest marker)
-Level 13 Critter, Beast and Magic.

Delza Plaguehorn - EPL
Level 14 Beast, Beast and Undead

Kortas Darkhammer - Searing Gorge
Level 15 Dragonkin, dragonkin... and dragonkin (Obviously never played pokemon...)

Everessa - Swamp of Sorrows
Level 16 Aquatic, Beast and Flying

Durin Darkhammer - Burning Steppes
Level 17 Elemental, Critter and Flying

[npc=63596] in Stormwind City seemed unwilling to offer quests Battle Pet Tamers: Eastern Kingdoms and Battle Pet Tamers: Kalimdor to any character on my account.

Starting a new low level character and then asking [npc=167032] in Stormwind City to begin the Outland campaign finally fixed the problem.