What you need is support for HFS / HFSPlus (HFS+) in the kernel. Almost all 2.6 distros ive seen have had both per default, and most of the 2.4 distros have em too. Even the default Slackware bare.i has it as a module. So, try your luck with any live disk / full blown distro, its most likely there, but as a module.
Thta oughta get you on the road, then just mount it:
mount /dev/hddx /mnt/mac -t hfsplus