After getting halfway through LFS, I feel it would be much more convenient if I could automate the process. Unfortunately there isn't much documentation on ALFS, so I don't know how to get it work right. Could someone give me a good place to read, or some pointers?

Another thing I was thinking about: if I sat down I probably could write a big bash script for my own computer. That would take perhaps 2 hours? If I can't get ALFS to work, should I write a PERL script instead? Cos in bash I don't think I could chroot or su, could I?

You can chroot and su in bash. Those two commands even allow for other commands to be run.

chroot NEWROOT [COMMAND...]
su - root -c COMMAND

So in reality, you could set up LFS with several bash scripts.
Although the problem is with su you may have a password prompt (although if there's no password set, there's no problem).

Most of the documentation for ALFS is in the alfs profiles rather than in the alfs package itself, in particular the config directory within the profile. The config directory contains xml files which you can edit to suit your setup. there is also a shell script called 'runit' included which launches the build for you.

HTH

Mad.