Everyone loves a paper plane. Here are over 30 designs -- simple planes for beginners, advanced planes for the ambitious, and wacky, unusual designs for those who just want to be convinced that anything will fly.
Another great book by Paul Jackson. I particularly liked the sections on trimming (optimizing) planes and creating your own designs. This book includes some interesting, easy to follow, plane designs from square and rectangular paper. There are even a couple of planes made from teabag wrappers! For more traditional-looking designs, from square paper, I recommend his 2012 "Origami Airplanes" book.