I'm really very new to Knoppix & Linux but here are a few suggestions. Try apt-cache search netselect-apt & apt-cache policy netselect-apt. "bash: netselect-apt: command not found" as far as I know means that it is not installed. I use Synaptic Package Manager which is a graphical front end for apt-get & makes finding & installing packages very easy for a newbie. Also here is a link for netselect-apt: http://packages.debian.org/unstable/net/netselect-apt
Max