how to get delays of a circuit under process corner in hspice?
The models from the fab will have information on the corners in the .inc file, such as the nfet.inc  You then just have to select the monte carlo option in the HSPICE configuration.  You should have a few options: fs, tt, etc.  

You basically just need to read the manual.   Page 486 will show you what each model means, and then you can setup the run from there.