The following is available for F12:

A set of patches necessary to make Fedora packages build for ARM.
A set of source RPMs from the base F12 repository which also includes packages that have been modified to build for ARM. (still being rsyned...).

If you then click on the base F12 repository link it goes to http://fedora-arm.wantstofly.org/pub/fedora/linux/releases/12/Everything/source/SRPMS/ and this results in a 404.