better world books may have a good sale for BF. They often have some good sales on used books.
Do you have a scholastic warehouse near you? I love to shop their sales (usually they have one beginning of Dec) Most things are 50-80% off.
http://www.scholastic.com/bookfairs/warehouse/
"Someday, I am going to go to bed without toys on the floor and sippys in my sink. Things will stay where I put them and I can have nice, fragile items on display. But when I do, I will look around with a wistfullness in my heart and miss the days where vibrant imaginations ran wild and there was evidence of life happening around me all the time!"