In order to build .deb packages, following debian packages need to be present
(installed): 
devscripts
pbuilder
dh-make
fakeroot

As root (or sudo) execute:
pbuilder create

Executing build-git-snapshot without any arguments will leave package and the
rest in some pbuilder dir, eg. /var/cache/pbuilder/result It is highly
recommended that --buildresult option is used.