I'm planning on posting the results of my widget build taken step by step. It's just a basic search widget using the Yahoo Search API but I did it in 3 parts. The hardest part was actually getting the scrollbar to work. Apparently as part of the design specs for widgets, Apple doesn't want you to use the Aqua graphics (oh no, that'd be too easy!) so you need to custom design elements like scrollbars. Fortunately, they have some sample code which ends up being pretty plug and play once you follow the directions enclosed in the HTML file.