DSOrganize is back! Please visit the official page. I am NOT the author, and CANNOT provide support. Since this is a free app, most likely he cannot support you either, if you cannot figure out how to make it work.

I’m mirroring it here because dragonminded apparently flipped out or something and deleted it off his own website.

Unfortunately, to compile DSOrganize source also requires a ‘libdt’ which appears to a simple date and time library. I cannot find a copy of this anywhere, so you may have to rewrite the library, or change his code to use standard libnds date/time functions. It shouldn’t be too hard.
Also, I didn’t find the source to libfb, which may pose a problem in the future. But it may be linked out there somewhere, I didn’t look too hard.
UPDATE: Missing files provided by Deathwind

Some related links:
http://dev-scene.com/DSOrganize
http://www.dcemu.co.uk/vbulletin/showthread.php?t=36519
http://www.dragonminded.com/?loc=ndsdev/DSOrganize
http://www.youngmx.com/forums/viewforum.php?f=11
http://dragonminded.blogspot.com/