This is a subset of the CustomButtons page and is valid for Opera 7.5 and above only. Simply drag these links to your Search panel or any toolbar and try them out, a requestor will pop up asking whether to install it (displaying the command the button performs to confirm 'what-it-says-is-what-it-does'!). If you don't like the button, you can keep it for later by opening the Customize toolbars... dialog and drag the button there, and/or you can simply right-click on it and "remove from toolbar". If you have trouble dragging these to your toolbar - make sure when you click the left mouse button, you move the mouse vertically only. Most of them were taken from Rijk's search fields & buttons.
There are two types of Search widgets - the button type and the field type. The button type is ideal for the Search panel and will act on the contents another field to the left of itself, while you might prefer the field type for the toolbars because they are standalone.