Unfortuantely near as I can tell right now there's no good "one link" going to just the Aftershows with them ordered properly like they were before. Because that made too much sense.
Going to the Mythbusters/Videos
page and clicking around on the "link folders" below will reveal them but I'm not sure how (or even if) they're organized. I hope this is a WIP since the old way was much more straight forward.
Here's a link for the Episode-Specific Videos
which includes the two Aftershows for the two teams (Kari, Tory and Grant spend a good deal of their segment explaining more BTS stuff on what happened) as well as some more high-speed shots, some stuff on the SynDaver and other angles on some of the tests.