The text below from: http://git-scm.com/book/en/v2/Getting-Started-Getting-Help
at the very end has... and you need in-person help, you can try the #git or #github channel on the Freenode IRC server (irc.freenode.net).
Could you please tell me how I can access to this site or channel to get git related hep when I need?
If you ever need help while using Git, there are three ways to get the manual page (manpage) help for any of the Git commands:
$ git help <verb>
$ git <verb> --help
$ man git-<verb>
For example, you can get the manpage help for the config command by running
$ git help config
These commands are nice because you can access them anywhere, even offline. If the manpages and this book aren’t enough and you need in-person help, you can try the #git or #github channel on the Freenode IRC server (irc.freenode.net). These channels are regularly filled with hundreds of people who are all very knowledgeable about Git and are often willing to help.