...I can't even find where to post a new topic. I don't see that toolbar on any of the forums.

You probably have listed "Recent threads". You can't start a new thread from there because the system doesn't know in what forum to start a new topic.

Choose "Forum" from the menu on the left and select the forum you want to post to. Now you will see a button "New thread" on the right at the top and the bottom of the topic list. Click it and you can start a new topic for the selected forum.

You can also click a topic in the "Recent threads" list. The buttons will show again and you can click it to start a new topic in the same forum as the topic you selected before clicking the button.