Wordpress Search Form Widget
The WordPress Search Form widget allows you to wrap an image theme around the search input field in the side bar. Activate this plugin and then add the widget to your sidebar. After adding the widget to your sidebar, you can change the theme and default field value.
This plugin comes with 4 theme colors: red, green, blue (default), and yellow. The searchbox.psd and button.psd are both included so that you can modify the colors, or you can create your own theme.

Default themes include are:
Red
Green
Blue (default)
Yellow
