Another method to "speed up the process" is to switch to alternative companies that do support Linux. For example,
eMusic has begun selling audiobooks that can be downloaded with their Linux downloader. The selection is smaller, but you'd be giving your business to a company that supports Linux-compatibility. As DRM-free, Linux supporting companies like that are more successful, the better chance other publishers will decide that the Microsoft-centric DRM isn't worth turning away whole segments of their audience.