Southern Barrens Quests

This one is indeed really easy. For those who don't know where to start, begin with Hunter's Hill and do all Quests you can find there. (The NPCs called "Honor's Stand Officer", in Honor's Stand, very close to Hunter's Hill, drops a Start-Quest item aswell, not sure how high drop rate but I got it on the first kill.) Just do exactly every quest you find and this won't be any problems at all.

Edit: It seems like the Start-Quest item from Honor's Stand Officer has 94% drop chance, so if you don't get it on your first kill, slay another one (or two) and you will most likely get it.

Good luck! :)

If you are stuck at Hunter's Hill being incomplete, go to /way Southern Barrens 37.65 16.63 Holgom
This guy has 2 more quests (You can see the ! marker if you switch to the Northern Barrens map) If you haven't done so yet, also do the 1 quest from the guy in the Tower

If you still haven't completed it, go to /way Southern Barrens 31.4 13.3 Nura Pathfinder
She will have 1 more quest that will lead you up the high road, and one more follow up quest (Holdout at Hunter's Hill) has you go to Hunter's Hill. This quest should then grant you the credit.

Was looking for list of quests, found this:

https://wow.gamepedia.com/Southern_Barrens_storyline#Horde