My favorite online bookstore, which sells new, remaindered books at big discounts is having a fall sale from Sept 8 to Oct 31, with Halloween and Thanksgiving books marked down an extra 50% off the previous discount:
http://www.bookcloseouts.com/default.asp?N=3291&promo=Fall+Sale&sort=p_TitleSort&dir=ASC&rid=081060There's over 1500 books listed in the sale. I have better luck narrowing the list by clicking on the categories on the left (History, Children's non-fiction, etc.).
If you haven't already used it, here's a coupon you can use to get $5 off a $35 purchase. In your shopping cart, enter the following code and password:
Coupon code: bookcloseouts
Coupon password: bargainbooks
(Expires Dec 31, 2005)