Aftermarket parts from Nissan?

[Love Your Z]

Hey guys, first excuse me if I'm posting this under the incorrect area, but i need to get this question out there.

I wanted to buy what is labeled a "Rear Deck Lid" Spoiler on Nissan's 370z accessories webpage. I called my local Nissan dealership and it didn't sound like he knew what i was talking about.

So i was wondering, of course i bring my Z in, and i was wondering what i do from there, Do i go to the parts section of the dealership and they have some sort of magical catalog of parts waiting for me to sort through?

Thanks in advance, for either your help, or your patience with what might be a nooby question.
-Alex
Edit:Here is the link, it's under the NISMO section,http://www.nissanusa.com/zcoupe/accessories.html.