Raptor Hatchling Drops
1) Darting Hatchling - Dart - Dustwallow Marsh - 100% assumed drop rate
2) Gun'drak Hatchling - Gundrak Raptor - Zul'Drak
3) Leaping Hatchling - Takk the Leaper - The Barrens - 100% assumed drop rate
4) Obsidian Hatchling - Vendor - Breanni - Dalaran
5) Razormaw Hatchling - Razormaw Matriarch - Wetlands - 100% assumed drop rate
6) Ravasaur Hatchling - Ravasaur Matriarch - Un'Goro - 100% assumed drop rate
7) Razzashi Hatchling - Razzashi Raptor - Zul'Gurub

These are the new minipets released this patch and easy ways to get them.

The Obsidian Hatchling you buy from Breanni in the exotic pets shop in Dalaran for 40G.

The Deviate Hatchling is the easiest to farm for high levels, it drops from Deviate Guardians/Ravagers, a tip to farm it quickly is to go into WC pull the whole top level, loot then walk out reset and repeat, i got mine after doing this 2 times.

The Leaping Hatchling drops of the rare mob Takk the Leaper who patrols the ridges in the northeast of Barrens, it is assumed that he will drop the pet every time but he has a long respawn rate, he is easy to spot as he is blue against the other purple raptors in the area.

The Darting hatchling is dropped by the rare mob Dart who patrols just south-east of Blackhoof Village in Duskwallow Marsh. He is as his name says very fast and it makes it easier to have a /tar Dart macro available.

Razzashi Hatchling drops from raptors in the raid Zul'Gurub

Razormaw Hatchling drops from the rare mob Razormaw Matriarch which patrols in the northeast of Wetlands

Ravasaur Hatchling is dropped by rare mob Ravasaur Matriarch which patrols in South-eastern Un'goro crater.

Finally the Gundrak Hatchling drops from the raptors *surrounding* gun'drak, not in the instance. However these raptors are not rare so the drop rate is significantly lower than those of the other minipets.

For all of these rares the /tar "mob name" macro helps a lot with finding your rares.

Happy hunting, hope it helps!