Once per day, you can earn three event tickets per account by completing the daily event quest, Honest Toil. You will also get a Gold quality Parcel from completing the quest, which contains better rewards.
As usual in events, the event tickets can be traded for special items by visiting the Impresario merchant
. The merchant can be found in Daggerfall in Glenumbra
, Vulkel Guard in Auridon
, Davon's Watch in Stonefalls
, or Belkarth in Craglorn