Often times I find that a jQuery plugin's download link may not be the latest and greatest. Lately I've been going directly to the source :)
You can browse the jQuery Subversion repository online. The nice thing is you can see exactly when the author last update anything by looking at the revision and age.
Click the file you want. A new Trac page will open showing you the source with line numbers, etc. Simply scroll all the way to the bottom of the page and click "Plain Text". This will open a plain text view of the source which you can then save locally.