Cingular SIM Card?

Shanew21,

It's best to activate the iPhone with the new SIM card that comes with the iPhone. iTunes walks you through an easy process of transferring your current AT&T account to the iPhone.

If you would like to copy the contacts off your old SIM card, you can take it into an AT&T store and they can copy them to a USB drive for a minimal cost. You can then follow the steps in the following article to copy them to Outlook and sync them to your iPhone:
http://www.wireless.att.com/support/knowledgeBase.do?content=KB81228.html

Hope this helps,
Jennifer B.

Contact information is not stored on the iPhone's SIM card nor can contact information that is stored on a SIM card used by another phone be transferred to the iPhone so you will not gain anything by using your existing SIM card with the iPhone. The iPhone ships with a new SIM card pre-installed so you might as well use this SIM card for the iPhone's activation with AT&T.

AT&T provides a service for exporting contacts stored on a SIM card in a format that can be used for importing into an address book such as Outlook's address book.

You might try a Google search to see if there is a utility available for this purpose.