a tarball is any file with the .tar extension, but usually .tar.gz
to unpack one type:
tar xvzf nameOfFileHere
it usually dumps into a directory created in the same directory as your tarball file. always look for a file called "INSTALL" in that directory and open it in your text editor. this file usually will walk you through the process. but, like the previous poster said, most things are available as files called RPM files and end with a .rpm
these files can be installed as root by typing rpm -Uvh nameOfFile.rpm
if all the dependent files are there, it will install. if not, a good place to find missing files is:
good luck. linux rocks.