If you can’t see any packages or extensions listed in the Magento Connect Manager (Downloader), I might just have the fix for you. First thing I noticed was  we didnt have pear installed (use this script to make sure your server is compatible). After I made sure the server was compatible, the extensions still weren’t listing. I found on this thread that you can enter the following:

magento-core/Mage_All_Latest

…into the “Paste extension key to install:” box on the Downloader. It will populate the list.