There is an achievement: Darkmoon Despoiler in Darkmoon Island quests. Players need to get back all 9 pieces of Darkmoon artifacts, which will have a chance to drop from battleground and raid farming. Please note that only the player who has the Darkmoon Adventurer's Guide that can gain the 6 Darkmoon artifacts from the raid. These Darkmoon artifacts are BoE and can be sold by wow gold on the AH.
You can pick up one quest from the Darkmoon artifacts, it will reward 15 pieces of tickets from 3 battlegrounds(each reward 5 tickets), and the rest 6 tickets except for 15 tickets of A Treatise on Strategy, others are all for 10 tickets. The quest can be completed once time per month and will acquire 80 Darkmoon Prize Tickets. You can exchange the pets, mounts or transmogrification gears by Darkmoon Prize Ticket.
Fallen Adventurer's Journal, Banner of the Fallen, Captured Insignia can loot from The enemy corpses in PvP.
The other 6 tickets can drop from different types of raid, like raid dungeons, 5 Man heroic raid.
Please remember to get these quests prepared before The Darkmoon Faire coming.