Definitely get Git/Mercurial set up sooner rather than later - it's actually very easy to get the hang of the basics and it will give you a noticeable productivity boost (having a decent history of everything you've done is surprisingly helpful at times). You can still use dropbox as a kind of backup for your repository - no need to muck about setting up servers etc.

If you don't mind going for mercurial instead of git then take a look at hginit.com. Then if you're on windows, go and install tortoiseHg.