Help Configuring a Section

I have 3 regions in a section that I want to include:

Sidebar
Preface
Content

I want the Sidebar to be 3 columns. I want Preface and Content to be 9 columns. So the Sidebar will display content from the beginning of the region and to the left of both the Preface and Content like this:

Sidebar Preface
^^^ ^^^
^^^ ^^^
^^^ Content
^^^ ^^^
^^^ ^^^
^^^ ^^^
^^^ ^^^

I can't quite figure out how to do this. I've tried various combinations and using prefix and suffix but just can't figure it out. I'd appreciate some help.

Thanks