PoSTeX is provided by repository from 2.0 version. i.e. You can download if you type below in Windows console.
|tlmgr --repository=http://sourceforge.net/projects/postex/files/current/2011 install collection-postex|
And, you can update by typing
|tlmgr --repository=http://sourceforge.net/projects/postex/files/current/2011 update --all|
when you use TeX Live 2011 (if you are using TeX Live 2010, put 2010 instead of 2011).
The documentation and apps are in the regular path.
e.g. you can put "C:\texlive\2011\texmf-dist" in place of $TEXMF$ if you are using TeX Live 2011.
Difference from the last version (1.0)
It is recommended to install official tug TeX Live distribution instead of Ubuntu repository. After the installation, don't forget to type
as the installation does not add the texlive path to the default execution path (PATH environment).
Then, you can follow the general procedure above. Applications for editing will be automatically ignored to be installed as there is no linux version.