If you side with the warrior Rakatan, then you'll be able to obtain this quest from warleader Garn, who stands at the ocean's edge in the north beach area. Once you have the quest in hand, head to the Temple Exterior area and walk towards the pillar in the southeastern corner; you'll be ambushed by five or six Mandalorians once you approach. After you unpause, move your crew away from the middle of their deadly circle; you'll be hit by cryoban grenades if you stick around.
Once they're dead, search the bodies for the Mandalorian head that you need to return to Garn. When you bring it back to him, he'll lead you to a chest containing some of the salvage that he's found over the years, including a thermal shield generator, a verpine prototype shield, a verpine zal alloy mesh heavy armor, and six thermal detonators. Not a bad haul at all.
If you want the loot, but don't want to take the Dark side hit from attacking the Elders, you can initially side with the warriors, complete this quest, then head to the Elders and switch allegiances.
Ll'awa of the Elders offers you this quest. In order to complete it, you'll need to pester the computer in the Temple Catacombs for information about the Rakatan's genetic structure; if you do so, and return to Ll'awa with the info, he'll give you a small tip for the trouble.