Tracfone is a ripoff.

I use Page Plus. They have a couple of monthly plans and pay as you go is between 4 and 10 cents per minute depending on how much you top up. It runs on Verizon's huge native coverage but does have access to roaming partners for 29 cents per minute in the rare case. A 10 dollar top up card will get you 4 months so when you are not in the States you are not loading lots of credits unnecessarily.

Go to howardforums.com for the best answers on prepaid though. It is like the flyertalk for phones.