Mage's Running Boots are light boots in Dragon Age: Origins - Awakening.
Dragon Age: Origins - Awakening Edit
Sold by Yuriah in the throne room of Vigil's Keep for 7 38 0.
The Golems of Amgarrak Edit
Can be looted from a Maimed corpse in the Deep Roads Grotto, just past the Runic Golem in The Golems of Amgarrak DLC.