I would look into a virtual machine :http://forums.augi.com/showthread.php?16879-Running-a-virtual-PC-on-a-Mac-for-AutoCAD-use

I don't have a mac but have had past success with other windows based programs on linux boxes using wine (https://www.winehq.org/), but cant realy help much in this regards as i haven't played with it in a while. 

I might also check into http://www.autodesk.com/products/autocad-360/overview web based CAD.