trying to install ethereal-0.9.11
 

I am running slackware 9 and i downloaded ethereal-0.9.11-i686-1.tgz and then i typed tar -zxfv <ethereal...tgz> and i got an error, then i did it without the -v and it extracted into three dirs. They are /usr /install and /etc but i dont know where to go from here and i cant seem to find any install instructions.

well you got yourself a slackware pre-packaged binaries which are installed differently than a regular tarballs.
as root you have to run
installpkg /path/to/*tgz
or use pkgtool to manage packages

ya got to remember,
tar z(unzip) x (extract) f (filename) v (verbose)
should be
tar z(unzip) x (extract) v (verbose) f (filename)
tar -zxvf ethereal-0.9.11-i686-1.tgz
and then the uncompressing would work.
Now, for the installation:
I would cd into the install directory and read the INSTALL or README file with VI or VIM and go from there.

Or, disregard all that and go to
http://www.linuxpackages.net/details.php?name=ethereal
and download a binary for your linux distribution.