Elliot...not Ellen
Anyway, if you've got DNS enabler doing its thing, then as far as I recall from my installations, there's no special ldap stuff to do. You just need to set up a DNS zone, create an A record for your mac, have your mac point to itself under network settings as DNS server, and then the installer should work.
EDIT: I remember having to feel my way through some of the Mac instructions, and I'm sure I was helped by previous experience with Mac and Unix, as well as DNS. So I understand your frustration but I don't personally have time to type up my notes in a usable form right now. Instead if you can just point to the instructions that you're following, describe what you've done, and what you see when it stops working, then I or someone might be able to give you a hand.
BTW, all my installs have been Network Edition trial versions. If you're installing Open Source, I can't imagine it would be much different, but I haven't set it up myself.