WoWDB

You can track your completion of this achievement using this script:

/run AddTrackedAchievement(11065)

You receive a pamphlet by talking to the Doomsayer and selecting the following option:

The end is coming!

Would you like a pamphlet?

I'll take a pamphlet

Notes: There is a 20-minute cooldown between acquiring pamphlets, and it is possible to receive multiple duplicates. Progress is NOT account-wide.

Fast strategy:

The cooldown can be circumvented by the player death mechanic.

1.  Place all equipment that takes durability damage in your bank. This includes any equipment in your character's bags since taking  Resurrection Sickness incurs a repair cost regardless of whether the item's equip status.
2. Find a Doomsayer near a graveyard.
   
   1. Stormwind: The pandaren area near Eastern Earthshrine.
   2. Orgrimmar: Valley of Wisdom, near the class trainers.
3. Speak with the Doomsayer and take a pamphlet.
4. Mount up and fly high enough that you'll die from fall damage (about 100 yards).
5. Release your spirit and talk to the Spirit Healer.  Click "yes" twice to take the resurrection sickness.
6. Fly back to the Doomsayer and talk to the NPC again.
7. Rinse and repeat.