A Google Web Search Help thread tells us how to change the iGoogle layout from the new tabs along the left-side of the page to the old style of tabs across the top of the page.

To bring back the old top tabs, just go to google.com/ig?hl=all. In the past, bring up the old top tabs worked by going to google.com/ig?gl=all but now google.com/ig?hl=all is how to get there.

Here is a picture of the old tabs:

Here is a picture of the new tabs:

Forum discussion at Google Web Search Help.