Sidebar moved to bottom

Hi
I’m new to WordPress but I’ve been using untheme for a short time and everything been going fine… until… I made a few alts to the blog pages, mostly adding Amazon widget html. I’ve just come to look at the home page and the side bar has been displaced to the bottom of the page. I have no idea what I’ve done to cause this. The sidebar seems fine in all other pages on the site. Any ideas how to correct this problem.

Web site: http://www.flyingpodcast.co.uk

Using IE8

Cheers
Steve