Just FYI. Chck out
Cyberguys.com - Computer Parts, Cables and Accessories. Hard to Find Computer Parts for Aircard compatable routers. They could be more useful than just an Aircard especially when you want to print to a Network printer.
When I think of an Aircard, I usually think of an item that fits into the PC card or PCMIA slot of the computer.
If USB tethering is an option, then an Aircard would not be required ad you can use your cell phone at the same time. The USB connection charges your cell phone at the same time too. If other people use the computer, then this is not an option.