If truly all you want to run is a coffee pot or other small appliance, I would recommend an AC inverter that you can hook right to your battery or plug in your cigarette lighter.
If your car is not near your site, you can also just bring deep cycle marine battery to hook it to. (this is actually a little better, as you don't risk running your car battery down)
A 10 cup coffee pot uses about 1200 watts, I would recommend a 2000 watt inverter, so as to give you spare capacity.
You should be able to pick up a decent DC/AC inverter for 150.00
Generator's will cost you quite a bit more for the same wattage.