I just restored my iphone 3GS, now it's asking me for...

Hi. I just restored my iphone 3GS in order to deleting all its old data. I did this because this actually was my cousin's iphone (He gave me it to me), so I had to erase all the data. Now I am very confused and so mad because it's asking me for something called "Sim card", and it's not giving me the option to just skip it. I don't have a sim card, my cousin either. So wath should I do in order to get this thing working ? I can't use it! there's no button to skip the activation of the sim card. I don't need a sim card because I just want to use the iphone as an ipod, playing multimedia content and surfing and installing soft through wifi. What should I do ? I have no option getting sim cards, I don't have it and I don't need it. What should I do ? is it now a useless brick ? What should I do now ? Will it blend ? it's a beautiful iphone, it does not has any scrats, looks like new.