Gilnean Hound
Cataclysm Classic - The Gilnean Hound can be found in the Ruins of Gilneas, in the Northgate Woods and the Northern Headlands. The area within the ruins itself is intact but ghostly empty, except for some sheep, a few butterflies, these hounds & some Highlands Foxes (tamable).
Easiest for a Horde to get, as the Ruins of Gilneas is located on Horde territory. At Pyrewood Village the gate in Greymane Wall is broken and open, but here are some horde NPCs, not high level, but still kind of annoying and challenging if you are a low level hunter yourself. I did tried flying and swimming to get to the ruins but got fatigue, so that wasn't the way in.
Ruins of Gilneas https://wowpedia.fandom.com/wiki/Ruins_of_Gilneas
Northern Headlands https://wowpedia.fandom.com/wiki/Northern_Headlands
Northgate Woods https://wowpedia.fandom.com/wiki/Northgate_Woods