You can read the book just from the official site:
http://progit.org/book
Or, when you translating, you can read the local progit source files with this progit::reader.
This is a web app. Written in Perl and using Dancer framework.
git clone git://github.com/progit/progit.git
git clone git://github.com/chunzi/progit-reader.git
cd progit-reader
cpanm --installdeps .
perl bin/app.pl