The Linux RPM system is so convoluted and difficult to use that I've had to resort to this page of notes on how to do things.
RPMs are a great example of how to make something actually difficult to use. For an alternative, take a look at the NetBSD Package System. It actually works, it is simple, and you don't need to make a list of "how to do things with it"... You just do them.
You need to be careful installing things if you need multiple versions on the system. Upgrade or Freshen (upgrade only things which are already installed) delete the old version of a package.
rpm -q -a
rpm -q -f filename
rpm -q -l package_name
rpm -q -l -p package_file.rpm
rpm -q -R -p package_file.rpm