I have a book listed that I would like un list. how do i go about it?

if it's just on your bookshelf then you jsut check the box and delete it from your shelf.  If it's a WL book then you'll have to wait until someone accepts it and then decline the request

On your Wish List, there is a checkbox at the left of the book title.  On your Bookshelf, the checkbox is on the right.  In either case, check the box of any book or books you want to unlist, then click on the Delete button at the top.  I don't think you have to wait for anyone to request a Wishlisted book on your shelf in order to unlist it.

If Gretchen posted an WL book, it will be posted directly to somebody's WL and she won't be able to delete it from her bookshelf. In that case, she'll have to do as Mary suggests - wait until it's accepted and then cancel the request.

or if you think you might want to list it later, put it on hold on your bookshelf by checking next to it an using the hold button.  you are not in line for fifo if you do this and when you 'unhold' you are back at the end of the list.  just saves you from re-keying the isbn later to add it back to your shelf.