Again, it is illegal for police to search, detain, or question you just because you refuse a search. But if the police proceed to detain, search, or arrest you despite your wishes -- do not physically resist. You may state clearly but non-confrontationally: "Officer, I am not resisting and I do not consent to any searches."Link (Thanks, Chris242!)
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.