Dotsie,
There's no freight involved.
The first link is for book sales in your area. They are usually libraries and schools (at least in my area) selling citizen donated books and/or library discards. I have picked up quite a few 'like new' books from our library sales. Our fee is $5.00 annually, then the books are $1 hardbacks, $50 softbacks up until the last hours, when you can buy a paper sack full for $1.00. The object of our library sale is to raise money for the library, i.e. computers, children reading room assessories.
Here's what I pulled up for MD. http://www.booksalefinder.com/MD.html#X4462

The second link is a vendor that buys books from you. You enter the ISBN from your book to see if they are looking for that particular publication. They pay the freight for you to send it to them and you get paid for the book. It works nicely if you have several books laying around you aren't needing anymore, but don't want to throw away or give away. Another thing to do with unwanted books is to donate them your local library for their booksales.