Hunt Goblins. You can find them in many places throughout the Dwarven lands.
Collect Goblin Necklaces (12a), Goblin Pendants (36a), Goblin Lord Pendants (33a) and Suspicious Memos. 4 memos will merge into a Suspicious Contract (100a) on its own, and once you have the contract you cannot get any more.
Return to Spiron at any time and turn in the items.