Shamelessly I refer to something I wrote some time ago ...
http://hem.passagen.se/dh1998/3d/gto/modelling02.html
:wink:
Its also good to read with meshsmooth (NURMS subdivision) is really about at
http://www.wide3d.no/tutorials/Car_nurms_01.htm
Generally its about packing your vertices tight together and create 3-point edges where you want it to be a sharp edge.