Second copy of NIS 2009

 I have the three PC license of NIS 2009, and I only have it on one PC.  I now have a second PC and would like to put NIS 2009 in it also.  I don't plan to put that PC on the internet, it will just be a stand alone PC.  Do I have to download the trial copy and then enter my key or is there a way I can download NIS 2009 to a CD and then use that CD to install on my second PC?  I understand that I won't be getting any of the definitions, I just want to make sure that PC is clean for the first time I start using it.  It was a used PC.