eGit User Guide

There is a comprehensive Users Guide for eGit which I forgot to mention. The Gettig Started section shows you how to set up a local repo, and also how to push/pull from a github repo.

While I'm here. If your eclipse workspace is in dropbox and you use it in more than one machine (say, laptop and desktop) then you should make sure to use dropbox's "Selective Sync" option and do NOT sync the .metadata folder in your eclipse workspace.  As this stackoverflow question atests, you should then be Ok. I have had this setup and shared a workspace between my laptop and desktop for over a year without any issues. The only thing is, I do have to 'import existing project' on the second machine after creating in on the first one.