The answer to your post Gary is somewhat complex. Internet and television signals are on different sattelites, and dishes can only be "Fudged" so far (By Fudged I mean use of an offset LNB) The shape of the dish affects how far
Now, The top internet provider is Hughes, and the oval "DirecWay" dishes can see up to 20 degrees either side of center, (The internet bird is always CENTER!) so if you get assigned to a bird that is at, say, 99 degrees W, then Direc TV's main bird is at 101 (2degrees) Which is a special case) and Dish is at 110 (11 degrees) and 119) 20 degrees) so one dish can do it all.
However if like me you are assigned to 83, Well,,, I could snag direc at 101 but I use DISH so I need 110 as a minimum or 110 and 119 both, this means I need 2 dishes.
Also the stuff hooked to the dish (MODEM for internet, Receiver for TV) is totaly different too, this is not a problem though, you can easily run 2-3 or more cables to the same dish (one per device mounted on the dish)