The subject of this article originates from non-canonical sources. To find out about what is considered "canon" see LOTR:Canon.
They are seen in the Fangorn Forest level where Aragorn rescues an injured one from Giant Spiders. After healing the elf he tells how he and his companions tracked a group of Orcs with the Mark of Saruman. Later Aragorn finds three of them fighting the Orcs and goblins. After helping the Elves they tell him that Saruman is building lumber camps in the forest and their Captain went ahead. Aragorn finds him fighting alone against three Uruk-hai scouts and a band of heavily armed Orcs. When they were defeated the Captain gave Aragorn Phial of Galadriel, then he goes back to Lothlórien.