As an Australian, guitar virtuoso Tommy Emmanuel doesn't seem to be much bothered about musical categories. Is his music jazz, folk, bluegrass, new age? Depending on the track, it can be any one. Like his mentor, Chet Atkins, Emmanuel is simply a guitar player, and on Little by Little, a two-CD set, he sticks mostly to acoustic guitar, playing mostly originals, tunes that he has used in concert but not recorded before. He is also mostly solo, although the double-disc length allows him room to share space with guests including singers Pam Rose (on her co-composition "Haba Na Hava") and Anthony Snape (on the folk-rock "Willie's Shades"). Among the covers are two versions of "Moon River," one with a bass countermelody, the other with an Emmanuel vocal, Carole King's "Tapestry," Atkins' "Mountains of Illinois," and "The Tennessee Waltz." Emmanuel plays fast runs, slows down for delicate passages, and adds harmonics on tunes that evoke players including Will Ackerman and John Fahey. He also likes folk-pop; "Papa George" needs only a James Taylor vocal to fit into that category. But Little by Little is a tour de force by a musician who usually leaves categories behind.