There are a couple of things you need to know about this achievement:
- Wasted roach is actually Resilient Roach. There is no Wasted Roach critter in WoW.
- Dancing Water Skimmers (and maybe Gilded moths) can only been seen before you finish the quests in Vale of Eternal Blosssoms - after that they are phased and you can't see them. However there are ways to get around this which you can find out if you read further!
One of the cool things about this achievement is that you can actually /love the critter after you have captured it in a pet battle. Which is awesome because I have every single one of these pets tamed in my pet journal so all my guildies could love them all and get the achievement. And that's how I got a lot of mine because I totally forgot to /love them whilst I was battling and summoned them after for the /love.
The second thing, is that all is not lost if you didn't get a Dancing Water Skimmer /loved. You can ask a friend who hasn't done the quests there to tame one with Critter bites (or ask a druid who has the Glyph of Charm Woodland creature) to bring the Dancing Water Skimmer to a non phased area so they can be loved by someone else. And for those of you who wanted to tame it but are now phased - never fear! The Dancing Water Skimmer is often seen as the 2nd or 3rd pet that come sto battle when you're battling other creatures in the zone (like Golden Civets and their kittens) so you can catch it that way.
Amethyst Spiderlings are found all through Krasarang Wilds. Clouded Hedgehogs are found throughout the Dread Wastes and also on in Townlong Steppes along the border of Dread Wastes.
Dancing Water Skimmers, as mentioned above, are found in the Vale of Eternal blossoms in water, especially in the western half of the zone, but only before you have completed the quests in the zone. They are also found in the Temple of Kotmogu battleground - look for them south of the temple in the water. Emperor crabs are found in the Dread Wastes in the southern seas and Zan'vess island, but I caught mine as one of the extra pets during a pet battle.
Gilded moths are found in Vale of Eternal Blossoms. I found mine as a second pet in a pet battle. There have been reports that there are phasing issues if you're trying to see it rather than battle it. Malayan Quillrats are widespread throughout Valley of the Four Winds, and the far North East of Krasarang Wilds, towards the border of the Valley of the Four Winds.
Leopard Tree Frogs are found in Jade Forest and are quite widespread. Golden Civets are often found wandering with their kittens just south of the Shrine of Two Moons in the Vale of Eternal blossoms. There is one particular pack that seems to spawn quite regularly.
Marsh Fiddlers are found in the Valley of the Four winds, around the various farms. I often saw them as a secondary pet in pet battles in the area. Mongoose are dotted around Townlong Steppes and often have pups with them.
Mountain Skunks are found in Stonetalon Mountains and Grizzly Hills! I didn't see any in Pandaria, so you don't have to love one in Pandaria, you can use one of the ones from the older zones. Luyu moths are found throughout Krasarang Wilds.
Resilient Roaches are found in the Dread Wastes, especially along the dark crater type parts of the zone (Dark blue parts on the map). Shrine Fly are found in the Jade Forest in a few spots along the more western part of the zone towards Valley of the Four Winds. I got mine as a second pet during a pet battle.
Sifang Otter and their pups are found in the rivers of the Valley of the Four Winds. Yakrats are found in Townlong Steppes in populated areas (around where people are with their Yaks). I have fond memories of my Yakrat, it was my first rare capture in Pandaria.