If you're getting an ATP you need your logbook. If you're just getting a type rating you don't need your logbook but you will still need to know your times to fill out IACRA/8710. Even if you're getting the ATP you won't need the logbook until you get to sim. Don't bring it to ground unless you don't plan on going home.

You also need a headset for sim and it's useful for your observation flights which you do in ground training. That's something they don't tell you in advance for some reason.