Blind stupidity!!
No, I decided that if it was a real 8GB for £19.99 delivered then it was a good deal. And then I would sell my 4GB one and make a good bit of the money back.
Thats what you get for being greedy, eh!
Anyway, the seller offered PayPal protection up to £500, so PayPal will definitely refund me my money. Its their guarantee. I have availed of this in the past. I still believe that the seller MIGHT get back to me, because I am sure he doesn't want the negative feedback.
Will keep you updated on outcome.
But I will learn and only buy from likes of Play, Amazon, MyMemory etc again.