Hi Robbo,
You've just described our learning curve of a few years back.
We eventually ended up with a Silent Running (or something similar...) Honda fourstroke. It comfortably powered a couple of fridges, chandelier, draught beer chillers, kettles etc - and even aircon one year. The noise was still a pain in the arse though. You can either surround it with those piles of tyres that are around the tarmac at MB, or - and this is what the Brethren do, take a fork and spade and dig a hole to put it in. This is hard work, but is very effective. One thing to bear in mind is the size of fuel tank, if it's getting heavy usage, you'll need to fill up the standard tank every 4 hours or so. If this is a problem, and in a large group it usually isn't, then consider an endurance version.
Alternatively, rig some sort of generator up to the back wheel of Uncle Alberts bike, and feed him on sausages and red bull for the weekend. He should light the place up.
H