This functionality has been built into the PS3 Homebrew Manager. We recommend you use that instead!

PS3 Update Finder allows you (on any OS) to find update PKGs for your games! Props to NzHawk for bringing this URL to the public and making the first awesome finder :)

Double click the URL to copy to clipboard or click "DL" to load in PKG Downloader

If this doesn't load for you please please let us know on the forums so we can fix it. Also make sure you have Java 1.5+!