The best you can do is gain access to some of the options in packages like
Cocktail and
OnyX . There are options here to change the bootup and shutdown screens to verbose, which will get rid of the white screen and show you what's going on.
Be aware that these packages also allow you to do all sorts of maintenance on your iBook as well, which can be a good thing if you're careful, or you can really screw up your machine.
As posted before, you really need to view OS X not as a UNIX system, but as an operating environment that uses UNIX under the hood. The whole thing is designed so you don't
have to get underneath.
Frankly, this is why I got away from Windows as my home machine's OS-- I spent almost 20 years in some capacity as a UNIX admin and I got tired of having to tune everything all the time both at work and at home. I love the fact that OS X handles everything for me underneath the covers, as it were. I love not having to mess around with settings just to keep my machine running.