Git is a revision control system, a tool to manage your source code history. GitHub is a hosting service for Git repositories. So they are not the same thing: Git the tool, GitHub the service for projects that uses Git. To get your code to GitHub: have look here : https://help.github.com/articles/create-a-repo
In the SVN analogy, Git replaces SVN, while GitHub replaces SourceForge
If this project of yours is new, then you can still commit to your local Git, then you can push to GitHub later on. You will need to add your GitHub repo as a 'remote repository' in your Git setup.
They seem to have something for Eclipse users : http://eclipse.github.com/
Otherwise, if you are new to Git : http://git-scm.com/book
