Oracle 9i is a huge complex with very useful, and most of all very secure applications. This document slightly touches the surface and is not intended to be a comprehensive guide. I hope that it can help solving some problems during the initial installation, but it is important to analyze your own situation and turn to more reliable sources.
Some of the operations could be executed manually using SQL*Plus. This could be a more flexible way to tune and set up the installation. I will leave this in more experience hands.
I haven't mentioned so many things, that are described in details in Oracle documentation itself. So explore the genuine source in depth!