Another update from me...
It's not the _full_ solution I was hoping for, but I did get somewhere. In the event anyone else could use this information, here's the best link of all:
This is aimed at those who wish to make changes to their keyboard layout in X. (I am still trying to comprehend the Linux keyboard outside
of X.) This article finally explained (clearly) what keycode and keysym are. I would mangle any explanation, so please read the whole article to get the full picture.
If any gurus are reading this, I think there needs to be more documentation that deals with _where_ my default keyboard layout is coming from. xmodmap -pke shows me what that map (theoretically) is, but I can get some strange characters by typing Alt+<character> which do not show in the keymap. These characters do not show at a virtual terminal, nor in a gnome-terminal. It appears to be xterm-specific. Where is it getting these from? Is this part of the Linux keymap? Where is that stored?
Why do I keep finding more questions than answers? *grin*