There are a lot of Pets that can be obtained out there. Many of them can be picked up simply with gold on the AH. There are also some that you have to get yourself if you want it. I will go over some of the available pets that not everybody may no about. This may help some of you who are trying to get to 100 or 125 pets with the new acheivements next patch. Although if you have that many pets, you probably already have these. So, here is a little list of pets to pick up.
There are a few new ones that you get as a result of a quest.
Firefly: If you do the Keeshan quests out in Burning Steppes, it will eventually lead you to this pet.
Mr. Grubbs: A small version of the ugly ass Giant Grubbs out in Eastern Plaguelands. First thing you need to do is get one of the zone buffs at one of the quest hubs. It will be the one that gives you loot bags. In these loot bags can be Mr. Grubbs.
Withers: This quest is in Ashenvale. Look it up on Wowhead. It is a long quest chain that eventually nets you a little treant pet. I dont know if he still has the same effect, but you can go through a body of water to make him grow significantly.
Snarly, Muckbreath, Toothy, and Chuck: Possibly some of the cutest pets in the entire game. These little bad boys drop off of the Shattrath Fishing Daily "Crocolisks in the City". You pick up the quest, go to Stormwind, fish up a Crocolisk and return. The best part is the drop rate is very good on this quest. I have obtained 3 of the 4 on Darraxus.
Strand Crawler: The Strand Crawler is a cute little red crab that drops in the reward bag for both the Cataclysm and Wrath fishing dailies.
Sunflower: This is a very interesting pet that sings to you. You can obtain this one by completing a quest chain in Hillsbrad. You will have to look it up on WoWhead for better info. Be prepared to take a few tries on some of the quests if you have not done them already. It is a WoW version of Plants vs Zombies.
Westfall Chicken: This is a classic pet quest and is still there. Go to the Saldean farm and buy a bit of chicken feed from him. Create a macro that says /cluck. Put it on your action bar. Find a chicken and spam the macro until he has a quest turn in. Give him the feed and get a pet!
Disgusting Oozeling: This is obviously considered a tough one to get. It drops from a bag that random slimes drop. The best place to farm these is the Swamp of Sorrows. In the water area around Stonard there are a bunch of oozes in the water that can be killed to get the bag. They respawn pretty quickly as well. My wife farmed up two of these for her characters in around 6-7 hours of killing mobs.
Sprite Darter: You used to do a quest to for Alliance. Now it is a zone wide drop. I recommend smashing the Yetis in the cave south of Dire Maul or the Ogres a bit further south.
Worg Pup and Spider: Both of these pets used to be a quest reward. Now they are a 100 percent drop in BRS. The Worg Pup drops off of Quartemaster Something Rather. The Spider drops off of the Spider Boss. Easy peasy.
Phoenix Hatchling: Possibly my favorite pet in the game. Fairly low drop rate of of Kael'Thas in Magisters Terrace. It drops off of Heroic and Regular as well.
Mojo: This horny frog drops in Zul'Aman. I picked it up on Darraxus and have been helping my wife and friends get it on their toons before the change to the instance. If you /kiss him he will whisper something dirty to you and turn you into his frog lover. You use Amani Hex sticks on the frogs around the middle pool to have a chance at Mojo. A couple of things. Make sure you have bag room as he jump into your bags. Second, the Hex sticks drop off of Humanoid Trash Mobs. Third, dont kill the bosses. If you dont kill bosses, their trash will respawn withing the hour. You can farm it all week if you want to.
Annoying Ass Fishing Pets: There are a couple of pets that can be fished up. The Magical Crawdad and the Giant Sewer Rat.
The Magical Crawdad can be fished up from the fishing pools around Skettis in Terrokar Forrest. You will get a blue item called Mr. Pinchy. He will give you three wishes apparently. I got the Crawdad on my first wish. I can certainly take a while to get the drop. If you dont have bag space, Mr. Pinchy will send you an angry email with the Crawdad attached.
The Giant Sewer Rat is a Giant Bitch that has never dropped for me. Fish him up in the sewers of Dalaran. If you dare try.
That is my short list of Pets. Go forth and horde them critters.