Search Amazon and Google Books for the books you own. Occasionally these sites offer a "Search inside the book" feature that allows you to search the text for phrases. Your search will either return a page number and, if you're lucky, the page of text upon which the phrase occurs.
Note that this is NOT a replacement for owning the books themselves, but it will save you valuable time searching for that elusive bit of trivia from early chapters when you're burning the midnight oil on a midterm.