I agree with Hooligan - spare yourself the emotional torment of parting with your books. As for cheap bookshelves, I used to have cheap Ikea bookshelves made of wood, but they did not last long. I know have metal bookshelves. And they were not even expensive, either, but the point it - they are metal and they are not going to go the route of wooden IKEA bookshelves.

Since you are packing and unpacking at the same time, you need color-coded sharpies and/or color-coded labels for the boxes. Or, go to UHaul and buy a set of tapes. Their tapes are color-coded AND show the name of the room on them; if you disregard the name of the room and just use colors, there will be enough colors for your purposes.