Classical guitar offerings on SACD seem to be few and far between. Some that look interesting to me (although I don't own any of these as yet) are:
http://www.elusivedisc.com/STOCKHOLM-GUITAR-UNIQUE-CLASSICAL-GUITAR-COL-SACD/productinfo/OPSAM22062/
http://www.elusivedisc.com/JULIAN-BREAM-POPULAR-CLASSICS-FOR-SPANISH-GUITAR-SACD/productinfo/RCASAM04606/
http://www.concordmusicgroup.com/albums/Art-Of-The-Guitar-SACD-60672/
http://eudora.nativedsd.com/albums/fernando-sor-guitar-sonatas
Although not SACD, there are a couple of classical offerings on HDCD from Reference Recordings by Roberto Moronn Pérez:
http://www.referencerecordings.com/FRESH.asp
http://www.elusivedisc.com/STOCKHOLM-GUITAR-UNIQUE-CLASSICAL-GUITAR-COL-SACD/productinfo/OPSAM22062/
http://www.elusivedisc.com/JULIAN-BREAM-POPULAR-CLASSICS-FOR-SPANISH-GUITAR-SACD/productinfo/RCASAM04606/
http://www.concordmusicgroup.com/albums/Art-Of-The-Guitar-SACD-60672/
http://eudora.nativedsd.com/albums/fernando-sor-guitar-sonatas
Although not SACD, there are a couple of classical offerings on HDCD from Reference Recordings by Roberto Moronn Pérez:
http://www.referencerecordings.com/FRESH.asp