You have to be inside the folder where the files where extracted to, to use the install command, but...as evo2 says it is not recommended to do it this way. There is another reason too and that is dependency hell. libreoffice also depends on other files like ure and uno and unless version 4 doesn't need them they are not included in your list.
It is better to let synaptic or apt-get work out the dependencies and it will install them. Precise repository (the site where the deb packages are stored) does not feature version 4; they are at 126.96.36.199 at the moment.
But there is hope. There is a type of repository called PPA at https://launchpad.net
They are "personal packages archives" and it so happens that there is one for libreofffice version 4.1; your luck! https://launchpad.net/~libreoffice/+...ibreoffice-4-1
To add a repository to apt sources you can directly add some lines into the sources list at /etc/apt/ In Precise these would be:
or even easier; in a terminal type (copy/paste):
sudo add-apt-repository ppa:libreoffice/libreoffice-4-1
Now you will find it with version 4.1 in synaptic. Just double click on libreoffice and it will choose an assortment of files and their dependencies.
You can also choose some extras, like the help files (for us Aussies it is libreoffice-help-en-gb), libreoffice-l10n-en-gb, libreoffice-pdfimport and others.
You also need to install java like openjdk-7-jre for some functions to work.
Hope that works out for you.....and don't hesitate to ask whatever...a few years into linux and I still have plenty of questions too.
See you mate