alibris.co.uk
Details: £5 off £50
SortFloorBooks.com
Details: They have discounted books and free shipping over 14.99 per order. They also have a 10% off holiday coupon on orders over 25.00 thru the end of december.
Use (HOLIDAY2008) as coupon code at checkout.
Fellowship Books
Details: 5% off your purchase of $50 or more