From the official Debian Internet site I read:
 A "network install" or "netinst" CD is a single CD which enables you to
 install the entire operating system. This single CD contains just the  
minimal
 amount of software to start the installation and fetch the remaining  
packages
 over the Internet.
To connect to Internet, I use ppp and a pendrive as modem.  It seems  
that the
minimal netinst doesn't install ppp, so I can't connect to Internet to  
fetch
the remaining packages.  Am I missing something important, or should  
conclude
that the network install is not for me?
Thanks for any help,
Rodolfo