do you have a VTEC badge on the back? does the valve cover say VTEC on it? do you have a strut tower bar? these are some the things that you'd find on a stock GS-R that you wouldn't find on a stock non GS-R.

if you want to know for sure, what's your VIN? does it have DC2 or DB8 in it? if so, it's a GS-R.