If you want more information try checking out the Linux Documentation Project. Linux is available in different flavors called "Distributions" this just means that someone else has gone through the trouble of collecting all the software you need (Including things like Wordprocessors, Spreadsheets, Web browsers, etc.). You can buy a Distribution CD in just about any book store (in the back of a book obout Linux), computer store or places like Best Buy .
Or, if you want, you can download it for free from the FTP site at ftp://ftp.cdrom.com/pub/linux For beginers I sugest the Redhat distribution, it's about as easy to install as Windows. If you prefer working from the Command prompt instead of a GUI; try the Slackware distribution, get the highest numbered one.
I run a small network at home, just 5 computers. One of them runs Linux
and functions as a gateway to the internet. It's up and running, dialed into the internet 24/7. It's running as a firewall with IP masquerading which allows all of the other computers to access the net over it's phone line. Just for fun I also run a webserver and an email server on it (not currently accessable from outside my house). It also runs a software package called Samba which lets it act as a file and print server for any Windows PC connected to my LAN.
All of the software needed to do this was included for free in the distribution (I'm running Slackware).
Robotics
The only Robot I currently own is an old Hero Jr. I sold off my others to raise some money for my EV projects.
I'll include more information here later.
My Page on Computers and Robotics