Did you find your installer?
Its Very easy to set up yourself.
... look up and go to "dishpointer" on google - pick your location, it displays in Google maps.
1) Select your satellite - for all the UK Freesat channels you need the Astra 2D satellite, you will see that its 29.9 degrees elevation (thats quite low to the horizon).
Screw or fix the dish where it can get a clear view of the sky at c.30 degrees, remember height doesnt matter, it can be mounted on the ground, its a clear sky that it needs, set the elevation to 29.9 as best you can - there is usually degree markers on the bracket.
2) Now on the dishfinder site drag the icon on the map to the spot you have placed the dish - the line drawn on the map shows the line of sight to the satellite, see where the line goes through an obvious point - (neighbours chimney etc) and adjust the dish horizontally to point at that (maintaining the 29.9 degree azimuth or vertical angle).
3) You stand a good chance of it working at this stage although its best to finally adjust the dish angle. Doing this depends on your receiver, theres almost certainly a signal quality meter that you can display on the TV, on Sky boxes its under services. It does take a few seconds for the receiver to 'lock on' so its not dynamic, you'll need to adjust and wait a second or two. You'll hear the sound before you see a picture.
- alternatively for the final alignment buy a satellite finder meter - it'll cost less than £10 in UK on ebay.