Apart from the mountain of material in the members area at LearnCigarBoxGuitar.com, I've been gradually building a stack of free stuff too. Check it out.
Try Before You Buy- the Course Demos
The first two lessons in the slide course. We start with the basics - playing a note accurately with your slide and getting started on your fingerpicking.
The first two lessons in the fretted course, covers hand position, holding your pick, fretting a note, all the good stuff
Again the first two lessons, here you’re looking at the basics again and a few simple tunes to get started with..
Ten Iconic Blues Riffs for 3 string guitar including TAB and video.
More Free Stuff
Specifically for cigar box guitar players this course will get you started on understanding music theory so that it's actually helpful. It's referenced throughout the rest of the site and will be useful for anyone interested in making music, but particularly crucial when you get to the more advanced courses and workshops.
Just for 3 stringers, use the filters to find just about any chord you can think of.
With all the extra options that extra string gives you you need a bit more information than sa simple chord chart, although there's one of those too.
How to cope with playing chords when you've only got three strings.
17 Blues turnarounds for 3 string guitar, with accompanying video.
A short Workshop for new players explaining the basics of the guitar and how to play it. A must have for brand new players.