Fireside Chat

Here's a list of all the NPCs, where you can find them, and the stages they require:

Arthorn Windsong - Druids of the Talon. Can be found in the Furnace.
Deldren Ravenelm - The Shadow Wardens. Can be found in the Forlorn Spire.
Dorda'en Nightweaver - Through the Gates of Hell. Can be found in the Sanctuary of Malorne, also at the Forlorn Spire
General Taldris Moonfall - Through the Gates of Hell. Can be found in Malfurion's Breach.
Commander Jarod Shadowsong - Through the Gates of Hell. Can be found in Malfurion's Breach.
Malfurion Stormrage - Through the Gates of Hell. Can be found in Malfurion's Breach.
Matoclaw - The Sanctuary Must Not Fall. Can be found in the Sanctuary of Malorne
Thisalee Crow - Druids of the Talon. Can be found in the Molten Flow.

I panicked slightly for a minute there, but after a little more research from the information provided above and the Firelands Wowhead Guide, I've been able to figure which stages they fall in. (I'm not sure on the correct order yet since I haven't actually completed it, but these should be the stages they fall under. Thank you Joejr82 for the location of the npc's. I included your input from above.)

Stage 1:
Matoclaw - The Sanctuary Must Not Fall Can be found in the Sanctuary of Malorne.

Stage 2:
Dorda'en Nightweaver - You can talk to him either before or after completing The Fate of Runetotem. He can be found in the Sanctuary of Malorne. Cannot be accessed in later stages!
General Taldris Moonfall - Through the Gates of Hell Can be found in Malfurion's Breach.
Commander Jarod Shadowsong - Through the Gates of Hell Can be found in Malfurion's Breach.
Malfurion Stormrage - Through the Gates of Hell Can be found in Malfurion's Breach. When I first reached Malfurion's Breach, I was unable to access any dialogue for Malfurion. He was outside the cave. I left the Firelands area, but when I went back through the portal, he was inside the cave and I was able to talk to him and get credit.

Druids of the Talon:
Thisalee Crow - Druids of the Talon Can be found in the Molten Flow.
Arthorn Windsong - Druids of the Talon Can be found in the Furnace.

The Shadow Wardens:
Deldren Ravenelm - The Shadow Wardens Can be found in the Forlorn Spire.

A reference to Fireside chats, a series of evening radio addresses given by former U.S. President Franklin Delano Roosevelt during the Great Depression.