A virtual CD-R or virtual audio device may well be the best you can do, but it introduces the problem of doubling up your compression artifacts. Every time you compress, you reduce quality. The ideal solution is something like jhymn, which doesn't work with current iTunes 6 builds. With iTunes 5.x, all it did was strip off the DRM crap, converting the m4p files to m4a, retaining all the sonic quality (or lack thereof) from the original.