This excellent New York Sun review of a recent New York City concert introduced me to the marimba virtuoso Makoto Nakura. The Villa-Lobos Etudes and Preludes for guitar sound like excellent candidates for transcription to this fascinating instrument. Unfortunately, they're not included in any of Nakura's CDs so far. Let's hope that's coming soon, though!
In the meantime, if you're close to upstate New York on March 2nd, check out this free concert at Binghamton University, part of the fascinating series South of the Border: Explorations, organized by the Binghamton Philharmonic's composer-in-residence Carlos Sánchez-Gutiérrez.