Introductory reading on firewall/iptables/etc for new Debian user?

[Richard Owlett <rowlett@cloud85.net>]

I will be using email, Usenet, browser and occasionally file 
downloading.
Nothing on my system should look/act like a server.
I want all programs to access the internet after explicitly 
asking for permission.
The response to the request may be:
   No
   Always YES
   Ask each occurrence