git: command not found (on OS X 10.5)
From the page you linked to:
/usr/local/git/bin
Is that in your PATH?
Open ~/.profile in your favorite editor and add the line
export PATH=$PATH:/usr/local/git/bin
This appends the item to your PATH variable (separarated by colons), so it's compatible with other commands that modify the path.
Had the same issue on mountain lion.
If yo're using XCode, run it. then go to XCode->preferences and install "Command Line Tools".
thats it, worked for me.
http://www.hongkiat.com/blog/mountain-lion-git-fix/