UPDATE: Finally found a second artifact! Ornate Weapon dropped from the new Hour of Twilight heroic dungeon, off of the second boss. Unlike the bg artifact, where what you loot is what you get to keep, this artifact popped up as a standard uncommon item that party members could roll on. Both Need and Greed choices were available to click but I chose greed, so I'm not sure if it's actually possible to roll Need on it or not. Wowhead says that you cannot roll Need on it. I think only those with the DMF item that allows the acquisition of said items/artifacts could see/roll on it.
As mentioned in my previous post, little is known about the DMF artifacts atm other than each starts a quest that rewards Darkmoon Faire tickets (5, 10, or 15). Unfortunately, they appear to be a one time turn in per month, or "monthlies".
Going on a hunch after reading this Wowhead comment, I tried my luck with bgs instead of dungeons on the PTR. Despite not being an avid PVP'er and going in with full PVE gear, I managed to loot an Adventurer's Journal off a body! Yay! My first DMF artifact.
After receiving a great question about the artifacts in the comment section of my previous post, I tested to see if these items are tradable. The answer so far is: YES.
You can sell these items on the AH, mail them, and (although I haven't tried just yet) trade them. These artifacts are NOT Bind on Pick Up, so long as you don't right click it and accept its quest.
What does this mean for pet collectors?
This means that if you have an exceptional amount of gold to spare and these artifacts are all up on the AH, you could buy and turn in one of each artifact to the Darkmoon Faire each month (probably, but I haven't tested it yet, so don't take my word as fact), earning a max of 80 tickets on top of the other tickets gained from dailies and profession based quests. It would yield THREE pets each week the faire is in town (without the artifact turn ins, you only earn enough tickets each week to purchase two pets). This would cut down the time to acquire all 6 pets by one month (or by one faire week)! Instead of waiting for 3 faires to come to town, you'd only have to wait for 2!
I'm still unsure where all the artifacts come from and how high the droprates are, but this is huge news for those who are seeking efficiency and "ease".
Anyway, back to the PTR I go. I'm going to see if I can collect even more artifacts and find other possible drop locations. :D