Replying to Turntables, mixers , ect?

one of my buddies has a pretty sick setup with turntables, he plays music from his ipod or computer, and then scratchs to the music that bumping just for fun when were like chillen out and smoking and shit, i was just wonering if anyone has experience with turntables, what would i need to get for a setup like that, my buddies and i are getting a house next year and we were thinking about adding it just to fuck aorund on when were bored