I hadn't actually thought to ask that but as Andrea was already kind enough to get me the wind sim card I think it might be a bit much to start asking for scratch cards as well. This is an ongoing issue and I think it would be rather unfair to expect people to go to such trouble.
Anyway, thanks to me using gmail and it having the conveniently placed adverts relevant to the viewed email I found this link:
Starmap PDF
So, it seems beppe was correct before...and rather quick seeing as this was only announced yesterday! From my simple understanding of this it means I can just buy an o2 topup here in the UK. However, I wonder how much the "handling charge" will be when converting it from GBP to Euro? I know Vodafone give a rather poor rate. Also, how do I add the credit?