We have released the retail version of Prey for Linux. You will need our downloadable installer, a valid and unique CD key, and a copy of the game. You can use either the three CD-ROM version, the Collector's Edition DVD-ROM, or a preinstalled copy of the Windows version, such as you would download from Steam. There is no boxed version for Linux, but any existing Windows version of the game disc will work. We have also updated the demo installer with fixes for all reported bugs.
Information on how to download the required files is located here. If you'd like to use the Steam version of Prey, as opposed to a non-Steam install, Blues News has posted Ryan Gordon's .plan file here, which has solutions to use the Steam version.