legally they have to supply mains powered items with a uk plug of some type, I've had some items delivered with an adapter ready fitted (mostly fixed lead items) and others they have included a separate uk power lead (this comes up on the invoice as a separate item with a price of 0.00. I'm not sure what they do with items that use a separate power adapter as i've only ordered 240v stuff so far.
what are you thinking of ordering?
Matt