What is the best way to buy data while visiting the US?

Episode 874 (1:00:18)

Chris from London, England

Since Chris has a GSM phone, the easiest thing to do would be getting a temporary SIM card from the AT&T store. The chat room suggests going to Wal-Mart or Best Buy to get a SIM card there, but data is expensive. It may be best to go get a cheap unlimited data phone with a 1 month policy from MetroPCS and then give it over to a friend when Chris goes back home.