How do I find books about a particular monster?

I have a couple of side quests to kill monsters of a particular type, and they say I should read up on them. I can double-click the quest in my journal, and the tracking symbol appears, but it doesn't mark anything on my map.

Is there any way to track where these books might be? Or do I just have to ransack the area and hope I find what I need?

Solution 1:

I am only at the first part of the game (Flotsam), and there is a book shop just opposite the Dwarven smith where there are books on monsters.

Solution 2:

The dwarf who does your hair and is the third poker competitor also sells books. You should have the nekker book if you picked up everything. They increase your knowledge to 3/3 instantly, whereas it takes a while fighting. Probably great for rarer monsters in small quantities.