Webportio is a website that offers 100+ free graphic resources for Adobe Fireworks (the collection is growing regularly).
Items include buttons, calendars, forms, ribbons, sliders and many other ones. They are very well-categorized so you can find a specific object quickly.
All graphic files are vector-based which makes customizing easier and have a good structure of layers.
Even if you're not a Fireworks user, resources can still be handy as they come in .PNG format.