Moving Sidebar from Right to Left Position

Hello,

I am working on the following wordpress installation:
http://www.coreslab.net/Dundas/

I have to move the sidebar from the right position to the left position and have no idea how to do this.

Here is a link to my stylesheet, sidebar and page php files.
http://eastcoasttechwriter.ca/wp-content/themes/blue-business-10/images/files.zip

Thank you.