|It is unlikely you can use the 3G device unless it is a USB device and the laptop has a USB port and you can get drivers that will run under Windows CE.|
Excel, like the OS is embedded in the ROM chip. If its not working then there is something wrong with the laptop. Can you load Excel without any files. Bear in mind the file format for the Windows CE version of Excel is different than for the desktop version. You may need a conversion programme to convert from one to the other.