It’s that magical time of year, when the bright, shining faces of college freshmen fall as they take their first look at modern textbook prices. Reader S., a manager at a college bookstore, read our post yesterday about custom college bookstore “packets” used to prevent students from purchasing their textbooks used. He sent us some tips about how to spot and avoid special profit-seeking textbook bundles, and how to actually save some money by…purchasing from the college bookstore?