Hawke finds a chapter of a book called Hard in Hightown II. It's an unauthorized sequel to one of Varric's stories. The quest mission is to find and destroy all copies of this work.
This quest appears in Chateau Haine after you enter the building. The First book will be on a bench beside the first guard you encounter.
There are a total of three books you need to destroy.
1. Chateau Haine Interior - Beside the first guard you encouter in the actual Chateau.
3. The Dungeons - After your escape from your cell in the dungeon, head west. Once you defeat the guards at the end of the hallway the book will be on the table.
If you decide to fight through Chateau Haine then the first book will be right after the Hard to Stomach quest. The second book will be in the room where you find Codex entry: A Library of Distinction on a table.Once the third book has been destroyed a treasure cache will be marked on the map. Its location is found in The Retreat after your fight with Cahir.