You can clone the repo with:
% git clone git://github.com/briandfoy/mastering-perl.git
Or you can browse it on github (which sometimes gives a server error, so just keep trying).
Github is popular with the Ruby folks, but we can't let them have all of the fun. I converted my CVS repos and put them there, and now I'm working through my SVN repos. (And, lazy web, is there a good way to fragment an SVN repo into many git repos? I have my main SourceForge account with most of my modules in the same repo, but now I want those to be in separate git repos, one per module).
And, now that I've looked at Ohloh again, I see that they support git repos.