You have mentioned that you were looking for a team that specifically is good against tamers.
Here is my default tamer team:
Flayer Youngling (i really hope they leave reflection alone)
Celestial Dragon (you have to have acquired 150 pets in order to get this)
Clockwork Gnome use against any beast, very helpful against Major Payne, darkmoon tamer and Ulduum tamer.
These three won't work every time, but some combination of 2 of these I use on most tamer fights.
Here are some great pets to add to your bench to bring in when needed:
Fel Flame The H/H variety has a lot of health and if you save your
Conflagrate to finish off a mechanical, you'll usually negate their rez.
Snarly Pet reward for fishing daily just outside Shattrath in BC. Any of the three are good aquatic pets.
the other useful pets have already been mentioned in this thread, but I'll mention them again:
Jade Owl - you'll need an flawless magic stone to convert it to rare, but it's a beast (not literally) against any aquatic pet.
Mechanical Pandaren Dragonling is a nice counter to magic pets. Use it against outlands master tamer.
Shimmershell Snail will be strong against any elemental pet in the game.
Yellow-Bellied Bullfrog Any frog/toad is lethal against undead. Combine lvl 10
Tongue Lash with lvl 20
Swarm of Flies and you wont fear any undead.
I don't think that there is a tamer in the game that is immune to some combination of these pets i've listed here and that's only 9 pets.
For Aki in Pandaria, I use my Celestial Dragon/Flayer Youngling and Jade Owl and it's an easy fight.
For Major Payne in Icecrown I use Clockwork Gnome, Fel Flame and Snarly and it's an easy fight.
For What's His Name in Ulduum I use Clockwork Gnome, Celestial Dragon and Flayer Youngling and it's an easy fight.
For the Tamer in Shadowmoon Valley I use Mechanical Pandaren Dragonling, Snarly and Flayer Youngling and it's an easy fight.
At this point i've gotten so that I try to use 2 pets to defeat the tamers and level a third and you'll get there eventually, in the meantime, try these 9 pets and you'll have no problem defeating the tamers.
Good luck.