I have OSX 10.5.8 running very nicely on my MSI wind netbook. The drive (160gb) is set up as one partition. I would like to put linux (probably ubuntu) onto the system. Is there a way of doing this without a complete reformat?

Simply put, how do I resize the OSX partition in order to install ubuntu into the space created?

Resize an OS X partition using OS X disk utilty. Then boot with Ubuntu install disk. Create some partitions from unpartitioned space. Install Ubuntu.

Some hints if you are planing to use GRUB as the only boot loader for both OSes:
be sure to install Grub to Linux partition, not to MBR
be sure to install an older GRUB version (so called legacy; if such option present), not the latest version.
Although the latest GRUB version allows direct OS X booting, it may be a very tricky thing to do

So I repartitioned the drive and installed ubuntu into the emptry space. When it got to the last screen on the installer I hit the advanced button and selected GRUB to be installed to sda3 (sda1 is the EFI partition, sda2 is the OSX partition). The install went fine, but when I restarted I got a flashing text cursor on a black screen, nothing else.

Did I install GRUB to the right partition? I'm not sure what's happened!

Some info about GRUB http://ubuntuguide.org/wiki/Ubuntu:Feisty#...ws_installation

Also check if the correct partition is set to boot (usually it should be the partition a GRUB is installed to).

I fixed it. I reinstalled and used this guide to sort it out. Works fine now...

http://www.dailyblogged.com/1028/booting-u...eon-bootloader/