Thanks, I was hesitating on using the American address with my credit card because the purchase might set off some flags with my cc company.
It seems some card companys flag it as an issue and some do not , about all you can do is try it and find out - I seem to remember Natwest(?) being one who 'complained' about it - if they do the way around it is to buy amazon gift cards (using your 'real' address) then use the gift cards to buy the US PSN cards