One interesting site for ideas is The Atomic Rockets page, which is loaded with pictures and hard-edged thinking about the engineering of SF. The emphasis is more on the Solar System pulp sci fi of the Fifties, but it's a fascinating place. Similarly, Heinlein's Have Spacesuit, Will Travel is hugely dated, but he did a lot of thinking about the design. And how does anyone reach dials and controls on the back of a backpack?