MacAttack -
No, the Joomla! team does not assume that -- since they list over 700 extensions on the site they manage, they obviously know people will add to the base install. When I started, it was not uncommon for me to start from scratch -- that might be your best bet. You can learn a great deal each time you install. One other thing I found when I started is that I "over did it" with the extensions -- I was like a kid in a candy store, if you know what I mean.
I hope you stay with us! Joomla! is great -- and I am certain you will get there. If you do decide to stay with us, might I recommend "The Absolute Beginner's Guide to Joomla!" <
http://forum.joomla.org/index.php/topic,47524.0.html >. This has excellent tutorials written by various community members. Helped me a ton when I started!
Also, as an aside, I know it is frustrating (trust me) to learn and that during that process, it gets even more frustrating hitting brick walls - so, it is perfectly normal to be upset. But, the paragraph kind of step across the "frustrated" line and headed right into "fighting words" in my opinion. It would be cool if you removed it (and my last paragraph can be removed, as well.) Thanks for considering!
Amy