try to find startx command with
find / | grep x
if this turns up no hits for startx i would imagine it is not installed if it dose work try to launch the binary
make sure you have
apt-get install x-window-system-core xserver-xorg gnome-desktop-envir…
i think you have xorg installed its just not in your $PATH to add it just type
export PATH=$PATH:/usr/bin/startx this should execute the binary startx in /usr/bin when startx is type in terminal "just for this session you need to edit .bash_profile…