Geez Houghy that's a bugger. Well seeing as they just moved in hopefully it won't be too long before they do get blinds.
An idea might be to collect as many blind and curtain junk mail brochures and bombard their mailbox everyday with them and hope they give in or get the hint.
My neighbour also has two spotlights that they usually leave on all night which are pointing too high and straight into my backyard so one night when I know they are out I might have to jump the fence and adjust them to point down a little.
Cheers Daniel.