IF you dont already have a version of Linux... I suggest you go get on and install it and learn it that way... It will stick in your head better and you get to play around with it...
Go to your local bookstore and get either Redhat or Mandrake Linux distro and load them on your PC... You will learn a lot! just by performing the install...
Yes, you will make many mistakes, but you will LEARN!!
For questions on Tar and RPM they are very similar... both compact/combine multiple files for easy transport over the net...
Goto a Unix site like
http://www.itrc.hp.com and query your question about tar and you will get alot of answers...
