At the Festival of Quilts, there was a stand with loads of things, including haberdashery type items. Each packet or reel of cotton, etc, cost £1!
There was also an Italian Button company with loads of large buttons. Good to keep in mind, as they are actually located in London (I think, but definitely UK). I would have bought some, but it would have been one of those situations where you end up buying something for an imaginary project that never happens. Because they are unique, you have to buy those kinds of buttons with something specific in mind.
However, these did come home with me!