Skoda Octavia GLXi 'S' plate Engine cutting out

[juggins]

I am experiencing that my skoda is cutting out when coming to junctions and stops. It used to be every now and then, but recently has got really bad. Today it cut out at least 10 times. Can anyone please give me some advise in what to do? I have phoned my local dealer and all they said is that it could be the spark plugs that need changing (which would cost �100), but i do not believe that this would stop the problem! Please help.