I used the "T-Mobile Even More Plus™ 500 Talk with FlexPay®" and added the featurephone internet "service"... I could only get edge anyway because of t-mobile's weird UMTS frequencies in the USA. I just had to set the proper APN and it worked (only edge, but that's just because I had a European GSM phone)

p.s. I used google voice for texting, no need for stupid text message plans