Back to 'hell's' post - do the three sat cables need three separate sockets, and how do they then feed into a sat box?
I just used 3 as an example, you can go higher (I think there was a pic online of someone with a 9-lnb setup
). Also you need an elliptical dish as a normal circular one is unable to focus things properly, and the more lnb's, the bigger the dish.
As far as the connections go, then you would need a "switch". which will then automatically select the correct LNB for the channel you select.
Personally I would go for a motorised setup instead as with a multi-lnb installation you are never quite aligned properly as you are compromising the alignment to allow the multiple lnb's to have some chance of being "focussed" properly. With a motorised system the lnb is always aligned with the focal point on the dish. Now, when you start on the motorised route things can get more complicated as you will need a positioner, a receiver for the different transmission types from different broadcasters, etc. It can get complicated but you would need most of the same equipment with a multi-lnb setup if you wanted to get the most out of it.
I used to have a 90cm Gregorian dish with a motor up it's tail and I could get around 500 channels in the NE of Scotland in the pre-Sky Digital age.