One of the best places (if not the best place) to find Flash extensions is at the Macromedia Exchange at www.macromedia.com/go/flash_exchange. Accessing the Exchange is easy. You can reach the site from Flash by selecting Help > Flash Exchange or by selecting Macromedia Flash Exchange from the Start page.
Extensions (including components, code snippets, or plug-ins) are created by Macromedia as well as members of the Flash community. Although many extensions are for sale, some are free. You will be are sometimes required to pay for extensions or components before you are allowed to download them, although this sometimes means that you get a higher-quality component or extension with some level of customer support as well. Some extensions are available from personal or commercial websites, blogs, or even forums.
Macromedia has published a list of companies that have created third-party extensions in the form of plug-ins for Flash 8 and earlier. A list of select companies offering plug-ins can be found at www.macromedia.com/software/flash/extensions. The extensions include plug-ins that create text effects, charts, image effects, and an extension that converts your 2D art and text into 3D animations.
You can find a more detailed list of where to find third-party tools and extensions in Appendix B.
You can also find more commands on the Flash Exchange by choosing Commands > Get More Commands from the Command menu in Flash.