Cell Phone Plans and cellular service - | Wireless from AT&T, formerly Cingular (Select Prepaid plans)
AT&T has two options for plans, Prepaid, and Pay as you go.
Pay as you go:
Get Started - | Wireless from AT&T, formerly Cingular
You buy cards of cash value, so a $25 card costs you $25 and is worth $25 in terms of usage. There are two options for voice:
$1/day IF you use the phone on that day + .10/minute.
$0/day + .25/minute
Text (SMS) is $.15 per message to send or receive. There does not appear to be any option to buy a text package.
The other option is "Pick your plan" - and IIRC this is much like regular (contract) service, but without the contract, and you pay for the upcoming month, instead of the current month.
Get Started - | Wireless from AT&T, formerly Cingular
These plans DO have messaging packages, listed here:
Text Message Packages | AT&T
No matter how you cut it, if you really want unlimited SMS, it's going to be $50+/mo with AT&T.