GIT tutorial on kernel.org:
http://www.kernel.org/pub/software/scm/git/docs/gittutorial.html

GIT for those who are used to centralized SCMs:
http://media.pragprog.com/titles/tsgit/chap-005-extract.html

Adding files:
git add *

Committing changes:
git commit -a "Log message here"

================================================================= NOTE ============================================================
GIT cannot store empty directories due to a design limitation.

Therefore, this command should be run prior to any commits to ensure your empty directories stick around:

find . -type d -empty -exec touch {}/.gitignore \;