To add anything in the right or left side bar you go to wp-admin > Appearance > Widgets > left or right sidebar > press small arrow on the right to expand.
In the main part you will see a tab which says PHP Code, drag this box into the opened sidebar. You can then press the small arrow to expand it and add your banner code from new paying ads or any other code.

You could also add paying ads to the main part of the pages, either at the top or the bottom by going to wp-admin > Pages > Edit. Find the page you want to add to, click edit and then add your banner code in the desired position making sure you are in HTML view mode if adding HTML.

Hi Andre

1. They will populate every single page if you post them as a widget in the right/left column. The only way around this is to install a plugin called widget context, which will allow you to specify which pages will show a particular widget.

2. Not sure about this, they certainly shouldn't providing you dragged over a new html box to input the Clickbank code.

3. I was a bit late replying to this and therefore now can't see the hyperlinks or lack of images. Sometimes it takes a couple of goes to input the code before it works, also make sure you are in HTML (not visual) mode when inputting code on a page.