The Beta5 DVD and NET ISO images for PowerPC have just been replaced by Beta5.1 ISO images. The only change is the way the ISOs are created - now they are bootable media.
There is a Delta-ISO from Beta5 DVD to Beta5.1 available in case you have Beta5 downloaded.
The media are available at the same place Beta5 is available: //download.opensuse.org/distribution/11.1-Beta5
Additionally new initrd and linuxrc for PowerPC have been uploaded in the PPC-HotFix directory.
These files are for Pegasos and Efika PowerPC systems if you want to do a network installation. Use these files and boot with the insecure=1 kernel parameter.
If you have further questions, please ask on the openSUSE PPC mailinglist,