Hi,
I have searched for this but most partition questions are regarding windows, so may i say sorry now if this has been asked before.

I have a machine with RedHat 9 installed, and i want to know if it is possible to resize an existing Linux partition, and keep the data integrity?

I have 3 partitions (hda to hdc in order) /boot, /swap, /
The reason i wan to do this is i wish to learn linux and have decided the best way for me to learn is to try LFS as it will give me an understanding of how it all goes. And in book 5.1 it suggests that for your 1st lfs to use an empty partition.
If anyone has any ideas then thanks, if it is not possible then nevermind.

Yes, you need to boot up with a rescue cd. Then you can use the command line tools e2fsck and resize2fs. For example...

e2fsck -f /dev/hda3
resize2fs /dev/hda3 8000M

You can also use GUI tools like qtparted