I am newly registered to the forum but have been lurking for quite some time. It is a great resource. As someone who is relatively new to the world of Oracle databases I would love to get up to speed quicker. Please PM me if you are available for a very basic 1 hour phone call (for which I will pay $125). I am trying to learn more about Oracle DB from the perspective of a DB admin, someone who has worked at Oracle, or someone who has understanding of various DB architectures. Please PM me.
One hour isn't really going to give you a lot of information. Save that money for books or food.
The first thing you should do is get familiar with the database concepts. Don't bother trying to memorize it or grasping everything in one shot. What this document will do is give you an overview of how Oracle's architecture works and get you familiar with the different terminology that's used.
If this is your first Oracle install, I would start off by installing a copy of XE first. It's pretty much automatic for Windows and Linux and this will get you up and running with an Oracle database. Read the 2 day DBA and Developer guides after that.
If you do decide to install a full copy of Oracle, oracle-base is another good website. The Oracle documentation can be a bit obtuse at times, so his guides cut down on the clutter.