Thanks for all your advice guys,
Decided my best option was to take the car to a tyre specialist and have the wheel balanced but unfortunately it would have seemed that the previous owner had fitted them without spacer thingie's and used the wrong wheelnuts, one was even missing but I think I was made aware of that by Colin when I bought it.
Consequently three of the alloys we're buckled quite badly, one so bad that the guy described it as "Nearly effing square" so I've just shelled out £600 on new set.
I'm just wondering if there is a worthwhile insurance claim on this ?!?!?
By the way I in no way blame Colin for this, he sold it in good faith and couldn't possible have known that the previous owner was a bit of a knob jockey.