Open D Tuning: A Player's Guide
Open D is the same tuning as Open E, a whole step lower, and I think it's the better default. It lowers four strings instead of raising three, it's easier on acoustics, and a capo at 2 gets you Open E whenever you need it.
The guide covers the tuning, the neck as a chord lookup table, working the bar for slide, and the blues moves that get around the F♯ string. There are 18 playable shapes, 12 full-neck chord maps and 8 scale maps, all in intervals so they move to any key, plus three phrases in tab, including a melody over the low D drone.
It's for slide players and fingerstyle players who want the open chord without tuning anything up.
16-page printable PDF, US Letter.