$30 option on T mobile
1. 100 min with unlimited text and web
2. 1000 min with unlimited text and 30mb of web.
VM $30
300 min with unlimited text and web but GSM locked
No great options.
100 minutes might be tight on your sole phone, but there are workarounds such as Skype...or bundling a digital voice home line with Internet and cable TV (if you'd have cable anyway).