I have a sky sat system in my van, what in particular do you need to know? The free sat service can also be obtained. heres my setup:-
Kathrein BAS 60 Flat Plane Dish (low profile and flat!)
Pace 1000 12/240V Sky Box
The sky box will receive all the free channels except Ch5 without a viewing card. If you want Ch5 and a few extra, then you need a viewing card and this is a one off payment of 25 pounds.
If you are already a sky subscriber, take the box and put it in the van, connect to sat dish, point to Astra 2D and away you go!
As for dishes, this depends on whether you want the service while touring in Europe. If not any sky dish will do for the UK, Popular choices are the 40in Multimo, the 55in Multimo is also available.
Free sat uses the same Astra satellite and all you need is a free sat box and any dish of your choice.
Its an absolute doddle once you have done it a few times, a compass is all you need. I lock on within a few seconds but heres a great site that will answer all your questions