Click here to reveal spoilers for Dragon Age: Origins - Awakening.
Namaya is a friend of Anders'; after his last escape from the Circle Tower, he asked her to look into finding his phylactery for him. During the Fifth Blight the templars decided to relocate them from where they were housed in Denerim, due to the threat to the city. Namaya has found out that the cache has been moved to Amaranthine and is waiting for him in the city to let him know exactly where it is. Judging by her harsh demeanor and the things she says to Anders, it's clear that she didn't want to wait for him, though Anders tells the Warden-Commander that she's usually nicer than that.
Namaya can be found directly across from the pitchfork stuck in the tree. She is just past the Crown and Lion tavern on the right-hand side if traveling counter-clockwise through the city. She is involved in a personal quest for Anders: Freedom for Anders and talking to her only while he is present in the party will trigger the quest.