Guitar Chords Magic - Guitar Chords Finder.
Here is a D Major Chord in Standard Tuning EADGBE.
Here is a D Major Chord in Open G Tuning DGDGBD.
How this has really been helpful to me as a novice guitar player is helping to learn the scales of the key I am playing in, which brings me to my next goto website.
Bob Craypoe's Dr.Psychotic, Strike A Chord.
Here specifically I'm looking at Bob's overview Chords in the Key Of G Major. Below you can see how Bob breaks down the Key of G Major and the chords in it!
Once I've got that recorded I go back to Guitar Chords Magic - Guitar Chords Finder. I now select the scale of G Major to see what notes I can play as a solo or melody on top of the Amin/Dmaj rhythm part I just played and looped. I can play any of the notes on the fretboard below and be "in tune" with the rhythm part I just played of the two chords Dmaj and Amin.
And so finally, I'll copy and paste the Scale from Guitar Chords Magic into the Chord Sheet from Bob Craypoe for a one page "cheat sheet" for playing in the Key of G major.
The result of this exercise is the song in the Soundcloud and YouTube links below, "Manhattan Sunset." In another post I'll discuss the production of the song (such as it is).