Article: Convert Your Unused iPhone Into A Pay As You Go Phone (No Jailbreaking Or Unlocking Required) -- AppAdvice

Convert Your Unused iPhone Into A Pay As You Go Phone (No Jailbreaking Or Unlocking Required)

Another One

http://osxdaily.com/2010/08/01/prepaid-iphone-setup-iphone-for-pay-as-you-go-plan/

And for iPhone 4

http://osxdaily.com/2011/03/06/iphone-4-pay-go/

Another How-To Plan

http://www.amirnaor.com/?p=49

AT&T GoPhone Plans

http://www.wireless.att.com/cell-phone-service/cell-phone-plans/pyg-cell-phone-plans.jsp

$10 Go Phone from Best Buy

http://www.bestbuy.com/site/AT%26T+GoPhone+-+Samsung+A107+No-Contract+Mobile+Phone+-+Silver/1450113.p?id=1218259762359&skuId=1450113&st=gophone&cp=1&lp=1