Mike @ Ambooked.com wrote this excellent post back in September 2011, but his sound advice on developing your own library book sale strategy still rings true and should be required reading by all online booksellers:
You can find his post by clicking on the link below:
I've found dozens and dozens of high-profit items on the final "bag day" of local library sales, putting hundreds of dollars of profit into my pockets for just a little bit of work. Very easy work.
While the library book sales don't usually kick into gear until Spring in my region of the county (the Ozark Mountain region), this is still very good information to bookmark.