A book I canceled two months ago came in the mail today...a little help, here?

If you canceled your order, you are not responsible for the book showing up. You got your money back, so there is no problem. Contact the place you purchased it and ask if they'd like you to return it. If they say yes, ask them how to return it C.O.D (cash on delivery--meaning they pay). This has happened to me and, because shipping is so expensive, I've been told to just keep the book.