You know there's a root index file at http://cdn.media.ccc.de/INDEX

Also you should use the CDN to redirect to the correct mirror

The web server returns redirect responses to mirrors that wget follows.

Just to clear this up: cdn.media.ccc.de is the new name for ftp.ccc.de. It was renamed because it does not actually serve FTP anymore, since HTTP can be load-balanced a lot better.

If you just use downthemall you get the advantage of mirror brain/metalink support.