with the new tmobile prepaid be able to roam into se iowa. i am asking because all the tmobile prepaid mvno's will not unless they have recently been updated(spot , ultra ).
http://prepaid-phones.t-mobile.com/prepaid-coverage will show the 2G and 3G/4G coverage maps for Prepaid and Monthly 4G. If you input an address or zip code on that page (the more information, the better), it will display the local coverage and if there is roaming in or near that area, it will also outline that. For Salem, Iowa, the 2G map shows 'Service Partner' in that area, which would be roaming coverage. Hope this helps.