I guess I'd probably be able to get used to it after awhile, but I'd certainly go through a period of withdrawal first. I'd really miss the easy access to information on anything I could possibly want, though. If I had a large supply of easily accessible books (at my house, not downtown at a library) that had information on any topic I could want, I could probably live.
Still, there's no easy way to replace the social interaction that the Internet can provide. Yes, friends in real life are great, but if none of them participate in a certain hobby (like Pokemon, for example), it can be awfully depressing.
People have survived for generations without the Internet, but now that it's here, it's extremely difficult to imagine life without it. Maybe I'd survive, but maybe I wouldn't. Either way, life wouldn't be as fulfilling.