I downloaded the latest Firefox version (.tar file) and I am wondering how you install it? instructions on the website don't give you even a hint how to start (what commands or whatever to use... same with Thunderbird). I could have used apt-get install but i wanted the latest version

1) Untar the file (Unzip):

tar -xvf mystuff.tar

2) Look in the folder if there is a bin file

3) Execute the bin file in commandline:

./bin

Normally it's better to install things using the package manager. For Firefox at least, there is an automatic update feature. Some distros disable this, but you should be able to turn it on (Look in Firefox preferences)

For both FF and Thunderbird, once you have unpacked the .tar.gz, just go to the folder created and type ./firefox (or ./thunderbird)

For anything not installed by the package manager, I generally use /opt--but any directory is OK (Some people put a /bin directory in their home dir, and then add that their $PATH.

Try:

If it runs fine, you may wish to move it to some other place and link it so it its visible to every user, like to opt:

Note1: The file name (firefox-2.0.0.11.tar.gz) is a suggestion. Substitute with the correct name for your firefox

Note2: I am linking firefox as "firefox2" to do not conflict with any firefox you have previously installed.

Note3: It usually is a good idea to stick with the firefox provided by your distro to keep consistency. Firefox should update itself anyway...

id did run ./firefox and i got the following error: ./firefox-bin: errror while loading shared libraries: libstdc++.so.5 cannot open shared object file: No such file or directory. What should I do next?

You need to install libstdc++. I think you can apt-get install it, but I would recommend you to open synaptic and search for libstdc and install the corresponding version (++5 in this case)