I forgot to mention this. I use Ubuntu. I know there are quite a lot of good books for RedHat Enterprise Linux system administration. But learning RedHat administration while practicing it in Ubuntu seems to be a bit silly. I'm looking for something that's more neutral. Something that can apply to most of the distros.
SCJP 5.0, SCWCD 1.4, SCBCD 1.3, SCDJWS 1.4