The best acoustic guitar recordings??

History of the Grateful Dead, Volume One (Bear's Choice)

Live recording, in memory of former keyboardists, nice recording blues and folk feel, reorded at Fillmore East New York.

Jerry Garcia and David Grisman: Shady grove: well recorded bluegrass very nice

jerry garcia and david grisman pizza tapes: ray but really earthy on the spot feel: great house of the rising sun version IMHO

John Williams: The Seville Concert Classical very nice recording and selection

Jack Rose: luck in the valley: folk music well record no vocals

Darkstar1 - Thanks for that...totally agree on Pizza Tapes...what a great album, a lot of fun, great story behind it, and great sound quality too.

I will look into Jack Rose...curious. never heard of it.

Also, I would add:

Wynton Marsalis & Willie Nelson. Two Men with the Blues
Buddy Guy/Junior Wells. Alone and Acoustic

Maybe an obvious one, but Muddy Waters , Folk Singer. Fantastic.

You seem to have many suggestions here so not sure if these gentlemen has been recommended already. I will however throw these in the hat:

Bill Frissell, I would try “Unspeakable” for starters as to me this album is definitely more vibrant and less safe than his usual, plus he is using more of the guitar and effects to the advantage of the overall sound. If you like this try some of his other safe albums. 
Also have you listened to any Michael Hedges?

Happy listening,
Chris

Mississippi Fred McDowell "I Do Not Play No Rock&Roll".
Also, his requiem album. No title, just Birth and Death dates.

Almost any direct to disc recordings of acoustic guitar