Quest Finder is off by default and can be enabled through the Options Panel (press Esc to access your Game Options).
When you press the Quest Finder Button in your Journal (it's on the last page of your quests) The Quest Helper arrow will now point to the nearest available quest. It will start with the current zone you are in, then expand to the current world you are in. If it doesn't find any quests in that world, you will need to move to another world and press Quest Finder again.
When you use Quest Finder, a window will appear telling you where to go and who to talk to, and the Quest Helper arrow will now point to that location.
another thing how to get to it too, click on your book and on the right side you will see buttons. click the button with a scroll and feather pen. then click on the task you wanted to get to. if it's not on that page, use the arrows on the left and right side of that page to get to others. if they are gray, that means the only quests you have are on that page.