Alright, I´ve managed to put the ads at the deserved place. One more thing:
At the top, there now is a space between the first sidebar widget and navbar and at the bottom, there is a space between the last sidebar widget an the footer.
1. Can you tell me how to fix that?
2. Can you tell me how to center the leaderboard in the content-area?
3. Is it possible to place the leaderboard between the preview/teasers of the posts on the homepage?