Hi, (excuse me if the terminology you use in US is not the same but I hope you get what I mean) Is there any provider of prepaid mobile sim cards that is cheap with no monthly payments (and no expiry) and has data (Internet) At the moment I'm abroad with a prepaid sim card that I bought a year...

Looking for information on purchasing and using a mobile internet card, the kind you plug into the USB slot of a laptop. I'm interested in something with good coverage (telcel?). What are the speed like, prices, and availability of contract vs pre-pay?