Something us Elder Scrolls Online players have begun realizing is that there is no official in-game trade or auction-house. While still a relatively new game, many players are hitting those points where they have some sweet loot they would love to sell or trade. Luckily, a third-party marketplace has been established to aid in players looking to buy, sell, or trade their wares.
CVG saw on the TESO Elite Forums a list of guidelines that players can follow when setting up online transactions. If you have any aversion to its legitimacy, Zenimax has actually endorsed it via twitter.
It should be noted that there is always some risk associated with a third-party route to trading, but no word from Zenimax has us thinking that there are no plans to implement an auction-house in the near future (I do hope I am wrong on this).