Learning About git

Free Online Pro Git book
Git User Manual
Git Reference

Install Git

compgit-osx-installer

Git Goodies

GitX git GUI

GitX is an awesome FREE history viewer made for OS X. It is a better way to visualize your branch and commit history of your git repository. However, power users (aka "cool kids") will probably only use it for history viewing while they continue to use the terminal command line for checkouts, branching, staging, rebasing and commiting.
GitX Home Page

Open in GitX

Open In GitX Finder Droplet

Git Tower

For those of you who just get panic attacks at the thought of using the Terminal, there is a commercial app for that:
Git Tower

Using git locally on a Subversion Working Copy