The "Star Wars: Knights of the Old Republic" series, from Dark Horse Comics, is chock full of Mandalorians. The latest issue, #24, includes Cassus Fett on the cover, using the on-going trend since "Attack of the Clones" of trading in any remaining mystery for unmasking the Fetts.
DarkHorse.com has, as usual, a 4-page preview of Knights of the Old Republic #24.
Zayne Carrick's murderous masters have hunted him halfway across the galaxy. Now, his run ends with him cornered in the very place where it began-in the Jedi Temple of Taris, the current headquarters of invading Mandalorian leader Cassus Fett!
The issue came out December 26, 2007 is available online at Things From Another World.
Issue #23 (4-page preview at DarkHorse.com) has a masked Fett on the cover, which came out November 28, 2007.
Issue #22 (4-page preview at DarkHorse.com) has Cassus, unmasked, available since November 7.
The 3rd trade paperback volume of the KOTOR series (4-page preview at DarkHorse.com) is available January 23, 2008.