WHat Alt-F version are you trying to build? What cvs version? trunk?
Following the wiki? What "board" target are you trying to build? As of RC4.1 all package download site was fine.
What specific tarballs do you need? I can create a download place at sourceforge for such unavailable tarballs. But read bellow.
Alt-F build system is based on buildroot-2009, and *only* the packages needed to build Alt-F have been updated. If you are trying to build something existing in buildroot-2009 but not used by Alt-F I can't help you.