There is also a linux-680×0 mailing list. See What Mailing Lists Are There?.
There is (or was) a FTP site for the Linux-m68k project on ftp://ftp.phil.uni-sb.de/pub/atari/linux-68k, but this address may no longer be current.Debian GNU/Linux has ports to Alpha, Sparc, Motorola 68k, PowerPC, ARM, IBM S/390, MIPS, HP PA-RISC, and IA-64. A Port to amd64 is being developed. There are mailing lists for all of them. See http://www.debian.org/MailingLists/ for general information, then follow the “subscription” link, and find the mailing list you are interested in.One of the Linux-PPC project pages is http://www.linuxppc.org, and the archive site is ftp://ftp.linuxppc.org/linuxppc.There are two sites for the Linux iMac port: http://w3.one.net/~johnb/imaclinux, and http://www.imaclinux.net:8080/content/index.html.