Entered info to one of those stupid free iphone things?

I know this is so stupid, but I'm a really paranoid person. I entered my info like address and name and phone number and email to one of those win a free iphone things. I don't know why, but what's the worst that could happen? I'm frankly not too worried because I guarantee thousands of other people have done it too, but still. & Please don't be mean about it, I didn't think about it at the time.

Thank you.

Added (1). Also, if you can't tell, my question is what is the worst that could happen?

Mail

The Direct Marketing Association's (DMA) Mail Preference Service (MPS) lets you opt out of receiving unsolicited commercial mail from many national companies for five years. When you register with this service, your name will be put on a "delete" file and made available to direct-mail marketers and organizations. This will reduce most of your unsolicited mail. However, your registration will not stop mailings from organizations that do not use the DMA's Mail Preference Service. To register with DMA's Mail Preference Service, go to www.dmachoice.org, or mail your request with a $1 processing fee to:

DMAchoice
Direct Marketing Association
P.O. Box 643
Carmel, NY 10512