Help find amazon coupon codes?

Anyone know where I can find a coupon code for amazon, it's for a book.. I was searching all over the internet for this book isbn 9780495567646 and the cheapest one I found was on amazon.com, I also tried half.com, can anyone help me find the book in another website for a lower price or possibly help me find some coupon codes, thanks!|||http://www.couponwolf.com/Books---Mags/A鈥?/a>|||you can try www.discountcodes.com but the listing for amazon.com is pretty long.