We compiled and downloaded under Linux last year using WINE, and will this year. I started in on getting debugging working, but backed down. Download the windows tools at the following URL, and extract them to the spot listed in the Makefile. The makefile should then download WPILib (last year's version, you can easily see where to specify the new source), patch it, and then compile it. I also included the patches I wrote to get doxygen to work to my satisfaction with the downloaded version of WPILib, and to get the Makefile for WPILib to actually work. Remove the .txt extension, and make a directory called bin where you are compiling, and put the patches there. It should be slightly obvious from the Makefile. Also, remove the .txt extension from the *ppc.txt files, and put those in the bin folder.
If you need any help getting it to work, or I forgot a step/file, I'd be glad to help.
http://zone.ni.com/devzone/cda/tut/p/id/5694