Brian,
You are absolutely right, but note these tiny considerations:
"Your MAC address is a UNIQUE, 48bit set of numbers (hex) attached to your Network Card or Integrated Interface."
Wrong
Many NICs and routers have a highly user-configurable MAC address. So this does not have to be unique
"But there ARE ways of obtaining the IP from someone regardless of direct connections or file transfers."
True
It even can be far more simpler. All noobs can do it.
E.g. Miranda IM has a open-source, official "Tip info" plugin that uncovers ICQ user's both internal and external IP address. You don't even need to talk to that person...just silently add the ICQ# to your CL and move the mouse pointer to the nickname
"EtherPeek (if you're willing to spend the big bucks)"
No need to spend any bucks!
Use the excellent, FREE and open-source Ethereal instead 
"Anything you do can be scanned, monitored, and traced to the very spot you are sitting."
In fact, yes. But using chained anon proxies can make tracing much more difficult.
Yours, Nederfox