The web search box and the URL address box have been combined in IE 9. If you want to use a search engine just enter your keywords in the same box the URL appears in (see 1, in picture).
The default search engine is Bing, but if you want to designate a different search engine do the following:
1) Click the down arrow to the right of the URL box (see 2, in picture)
2) Click "add" button at bottom of list (see 3, in picture)
3) Move cursor to the right to scroll to your favorite search engine. When you see it, click the icon.
4) Click "Add to Internet Explorer" button.
5) Check the "Make this my default search provider" box. Your done. IE will now search the engine of your choice.