Bravo FAQ and Tips and tricks
How to Change the Home Page Widget Images
the easiest is probably to upload images replacing the images that are currently there. The images are:
http://yoursite.com/wp-content/themes/Bravo/images/home-bottom-left-image.gif http://yoursite.com/wp-content/themes/Bravo/images/home-bottom-middle-image.gif http://yoursite.com/wp-content/themes/Bravo/images/home-bottom-right-image.gif
and the size is 93x80px.
You can then use text widgets as usual to add content to the areas.
If you want to insert images and have text wrapped around it, it may be the easiest to generate the code for that by using the "Write Post" panel (not to publish a post, but to make use of the advanced editor functionality), and when you're happy with the result, change the post editor to html view, which will give you the html code you can then insert into the widget.
Or use a plugin, such as: http://elementdesignllc.com/2009/09/wysiwyg-text-widget-editor-for-wordpress/