Update: I just received word that theÂ e-Shop is back in business.
The Blender.org e-Shop is still running on the 'old' server which used to host the www.blender.org website: the XServe. After moving the shop to a new server the admin team found out that it was experiencing technical difficulties. Because of that, the shop has been shut down as of last Sunday. In fact, the entire blender3d.org domain has been deactivated, so some rewrites (like mediawiki.blender3d.org) have also ceased to work. Use the blender.org links instead - they'll still work.
The team is working on a solution and we expect the shop to be back any day now.