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As glc pointed out, WiFi is becoming quite prevalent in the US, and much of it is free. Your motel will likely have it, if not for free in your room then for a fee in the lobby somewhere. During the day, you can stop for a cup of coffee at any Starbuck's and many other coffee shops or cafés and WiFi will be available. Finally, many local libraries will offer not only WiFi but free or low cost use of their terminals. My personal preference is to sit outside libraries which often have small parks associated with them that are still within range of the library's link
AZBuck