I looked at a few other pages and Peter's suggestions seems to be as good as any.

The Introcuction to Home Networking Link looked like a pretty good place to start. I liked the example diagrams of you most common layouts a little deeper down in that section. Nice simple diagrams.

It's a really, really broad topic to just start into a conversation on so read until you fall asleep then come back with questions.

With great power comes Awesome irresponsibility.