The answer is in the question my child....
sh: line 1: pkg-config: command not found
*** can not find package gobject-2.0 >= 2.0.0
*** check that it is properly installed and available in PKG_CONFIG_PATH
The PKG_CONFIG_PATH is the path that pkgconfig looks for package configuration files (*.pc files). These files contain information on where the libraries etc of packages are installed (note: not packages in the same way as .rpms and .debs, but in the utility pkgconfig sense).
Where is gobject-2.0.pc? Is it on your system? Look in /usr/lib/pkgconfig and /usr/local/lib/pkgconfig (maybe /usr/X11R6/lib/pkgconfig as well).
Which of the aforementioned directories exist on your system?
If you do not have gobject-2.0.pc, do you have a glib-2.0-dev type package installed?
What is your PKG_CONFIG_PATH variable set to? Does it exist? (Use "set" at a prompt to find it)
If /usr/lib/pkgconfig and /usr/local/lib/pkgconfig both exist, it can't harm to add something similar to the following to your .profile file if the directories exist: