Search Google. There are some nasty links out there, altought they do not appear to be recent.
If you are looking for Free Software CAD, check out Qcad at Ribbonsoft. I would not want to run Qcad professionally, but it is adequate for CAD work for you own home renovations.
If you are willing to spend money, VariCAD is available, and is supposed to be quite good.
If you are willing to spend a lot of money, UGS is available for Linux, and Pro/E is no longer available.