Are We There, Yeti? - (Step 3) Take Umi's Mechanical Yeti and scare her friends with it:
Legacki in Everlook (Winterspring)
Sprinkle in Gadgetzan (Tanaris)
Quixxil in Marshal's Refuge (Un'Goro Crater)
When you are done, bring the Mechanical Yeti back to Umi.
In Good Taste - (Step 2) Marin Noggenfogger wants you to speak with Sprinkle in Gadgetzan.
The Hinterlands Horde Quest
Message to the Wildhammer - (Step 1) Otho Moji'ko at Revantusk Village in the Hinterlands wants you to slaughter 15 Highvale Outrunners, 15 Highvale Scouts, 15 Highvale Marksman and 15 Highvale Rangers. Return to him when this task is complete.
You can find the Highvale high elves at the Quel'Danil Lodge in the northwestern region of the Hinterlands.
Alliance & Horde
Screecher Spirits - (Step 1) Capture the spirits of 3 screechers in Feralas, then return to Yeh'kinya in Steamwheedle Port.
Vyletongue Corruption (Horde) Fill the Coated Cerulean Vial at the orange crystal pool in Maraudon.
Use the Filled Cerulean Vial on the Vylestem Vines to force the corrupted Noxxious Scion to emerge.
Heal 8 plants by killing these Noxxious Scion, then return to Vark Battlescar in Shadowprey Village.