ok i sent a book off on sept  19 and it never got to where it was going. i do have a us postal service delivery comfirmation.  paperback swap sent me a notice that it was lost and i would not get the credit for it.  what happends if the book gets delivered in the next couple day.. have i lost the credit?

Chances are the book WILL turn up.  I've had a couple books be declared "lost" only to have them turn up in a week or so.  You will still get the credit, no matter when it turns up.  One thing I'd do if I were you is to PM the member the book was sent to just to verify that they have not received it. 

USPS delivery confirmation is (unfortunately) meaningless without also having PBS delivery confirmation in terms of getting your credit.

If you PM the member, you might mention that they should wait at least 2 more weeks before ordering the book again -- this is a Help Center recommendation to avoid them ending up with two copies.

Hope it gets there!

if you sent the book to a new member, perhaps they didn't know to come in and mark it received?  or does the DC you used not show that the book has been delivered?

very rarely does it take this long to be sent, but I know I've got 3 deliveries coming to me that have taken about 2 weeks and nothing has taken this long before!