Magento Connect
Third-party extensions that are offered to the Magento community are, for the most part, listed in a special section of the Magento website called Magento Connect (http://www.Magentocommerce.com/Magento-connect/):

Let's now review some of the features of Magento Connect, as they relate to researching possible add-ons for your Magento installation.
Searching Magento Connect
At the center-right of the Magento Connect home page is a search field. As with any intuitive search, simply enter in one or more keywords. You can also select the specific version – which Magento calls a platform—in the drop-down menu to the right of the keyword entry field. As shown in the following screenshot, we are searching for any extensions relating to sales:

Search field in Magento Connect
Furthermore, we can narrow our search to the specific Magento platform, such as the one on which this book is focused: Community.
The results of our search can be further refined by identifying extensions that are...