Prepaid cell phones with free nights and weekends?

I live in Oklahoma and I live in an area where I’m not able to get a lot of good cell phone carriers. I am looking for a prepaid cell phone carrier that gives free nights and weekend minutes. I looked at UAlltel and they had the perfect plan for me, but in my area we’re not able to get UAlltel. So, does anyone know of a prepaid cell phone carrier that will allow me to get free nights and weekend minutes? Or does someone know of a prepaid plan that is similar to Alltels? It doesn’t have to be available in my area as long as they don’t charge for roaming.

A little advise,do the homework before you buy.I got stung by T-Mobile