Everything from David Qualey. He needs more attention.
Everything from Bert Jansch. No explanation needed.
Other interesting acoustic albums that just came to my mind:
Pat Metheny - One Quiet Night
Pat Metheny - Watercolors
Nick Drake - Pink Moon
Nick Drake - Five Leaves Left
Nick Drake - Bryter Later
Michael Hedges - Aerial Boundaries
Michael Hedges - Breakfast in the field
Michael Hedges - Oracle
John Renbourn - The Black Balloon
Stefan Grossman & John Renbourn - Under the Volcano
All Stuff from Thomas Leeb
Justin King - Le Bleu
Eric Roche - Spin
Empyrium - Weiland (Except the tracks with vocals)
Empyrium - Where at night the woodgrouse plays
Ravi Shankar - The Spirit of india
Paco de Lucia - Iberia de Albeniz
If you need more, you'll get more..