I don't text messages and I doubt I would use the internet that much. If I did need it, I could always use a wifi connection. I don't really want to unlock it, but will if I have to. I'll see what they say when I buy it.
No. I believe AT&T makes you use a data plan with any iPhone or PDA they sell. It makes sense to me, considering you are buying a phone that has internet, youtube, email, stocks, weather...etc.