I'm just writing a guitar part in midi.
It's kind of wonky for me to figure out all six notes a semitone at a time, but if the chart doesn't exist I'll try to make one for myself. Thanks for the information and links - it really helps me

So, first I'd suggest an orchestration book if you have the motivation.
Second: http://www.dolmetsch.com/musictheory30.htm

Third, guitar is a transposing instrument (pitch sounds an octave lower than written).

This has the basics of the instrument (ranges, etc) http://www.musicianwages.com/music-notation-for-guitar/

You bought a MIDI guitar without knowing how to play a guitar? Or you're writing a guitar part with MIDI?

There's open chords which aren't that consistent. For these just look up a chord chart and figure the notes from those. (Standard tuning is EADGBE, count up a semitone for each fret)
And then there's Barre chords. Basically: root, fifth, octave, third above octave, fifth above octave, second octave. The root note will be (assuming standard tuning) above E2 and below the max number of frets the guitar has (usually 20, 22, or 24 or so). Although the lowest note can go to D#, D, C, etc if the guitarist uses a drop tuning. Can even go down to an A1, but you rarely see that outside of deathcore
There's also the "power chord" which is just the lower three strings of a barre chord (root fifth octave).

I'm looking for a chart that displays common fingerings for guitar chords in a regular notation like for piano. Does that exist?
I don't play the guitar so I don't know which notes go in which octaves