Yesterday I was on my way to raid and I thought I'd make my silk while I was flying nearby and inside my cocoon was an Imperial Moth! This is one of the two pets you can find inside the cocoon you make as a tailor.
And I went to Darkmoon Faire to get the Darkmoon Glowfly which is found all over the island. If you have a problem with finding one, try looking at the top of the hills, which you get to by running along the mountain top as you zone in. However, I noticed that there is a Crow pet that comes as a secondary pet - not capturable! It must be a bug, because the Crow is in the pet journal! Very annoying :( (Edit: 4/12/12 - they've fixed it! I now have a Crow)
Camped for ages trying to get an Anodized Robo Cub. They're found in Winterspring around Everlook, and I haven't seen them as a secondary in a battle (because I went around killing every pet that was within 20 seconds of flying around Everlook). However, I think that they do appear every few hours - Souglyy got one, and so I went back 2 hours later and waited and 2 spawned and I grabbed one.
This one is a pest to get when you're Horde! They spawn in Gnomeregan and also around Gnomeregan (such as the Airfields) but I only found this one and it was inside the gnome starting room in Gnomer. Had to die to get in there and corpse run at the max range inside Gnomer to make sure the guards didn't one shot me - they WILL one or two shot you!
Finally, another pet to capture in Deadwind Pass! This one is around at all times of the day around Karazhan, and can even be found on top of the towers themselves. Pretty common so wait around, they will keep popping up if you go at first and none are there.
This drops from Golemagg in Molten Core.
Found near the Alliance town of Toshley Station in Blade's Edge, I found mine just north west of the town. Don't get too close if you're Horde, you will get flagged and then some alliance idiot will gank you.
Drops from Magmadar in Molten Core, it's a nice imp pet to have if you don't have a Gregarious Grell.
Gosh people love camping dragons! This doesn't spawn VERY often, and it is found in the Savage Thicket where the protodrakes spawn in Sholazar Basin. When I was waiting there, only one spawned. I have heard that if you go around clearing the other pets you might have a better chance of this respawning. And don't listen to the tooltip of the pet, didn't see any around the coast.
Lots of people camping this one. Found in Tanaris outside the Caverns of Time, and also down inside the CoT main area. I found my first one outside the instance at the entrance to the area, but I killed it :( The next one I found a day later spawned right in front of me as I was waiting down near the Quartermaster.
Found in Kun-Lai mountains, pretty common in the mountainous parts.
Get your library book near the Dalaran crater in Old Hillsbrad. I guess the Dalaran mages left some books behind in their rush to move to Northrend.
This spawns in Coldarra in various spots. If you're patient and wait, it will spawn. I saw a few and managed to grab a rare, and then did a CRZ invite to Ratshag so he could get one too.
I thought this would be more common, it's found in Feralas in Shatter Scar Vale with the other yetis. Was the only one there when I went back on the third look.
This drops from Razorgore in Blackwing Lair. If you are well geared and deal with the adds, you can solo it. Otherwise, take a friend with you. It took me 3 goes of mind controlling Razorgore to get all the eggs so if you and Razorgore can last that long, go for it!
Drops from Viscidus in AQ40. Make sure you bring someone who has frost attacks or you won't be able to kill it. Mages, DKs, shamans are all good choices!
Wish me luck next week farming raid bosses again! And good luck to everyone trying to get their pets - I would say just be patient :)