WoW Wiki's BT Quest list page wow powerleveling Head's BT page with map showing quest giver locations. Step 2: There are quite a few quests in Borean Tundra that involve items to continue the chain, but only two that are started by items:

Massive Moth Omelet? (H) - On the cliffs near the cave southeast of Warsong Hold, a massive glowing egg needs to be delivered. No chain, small reward, but there you go. The Honored Ancestors - A four part chain started by, well, a giant talking rock in southwest Coldrock Quarry. You can't miss it. Step 3: Commonly missed wow powerleveling quest lines in Borean Tundra. These chains below usually account for players not being able to finish this Achievement.

D.E.H.T.A. Encampment - There is an easily missed series of quests in the middle of the zone that has you striking back against Nesingwary and his animal-killing ways. First comment in this WoWHead thread has a run down of all the quests in the chain. It also gives you an Achievement. Bonus: Cenarion Expedition faction gains.
Coldarra - This is the island off the west coast of the mainland. There are a series of quests at the Transitus Shield there that will help you top off your quest list. Also it gives you the lore behind The wow powerleveling Nexus instance. Winterfin Retreat - You get to save murlocs, chase murlocs, even dress like one. A quest chain not to be missed. Head to the northwest coast and speak to King Mrgl-Mrgl. Also, more Cenarion Expedition faction.