Here's the deal.  A few weeks ago, someone requested a book from me.  Like a dummy, I accepted the request, printed the wrapper, and then went to find the book.  However I could not find it.  So when I reached the final day to post that I had mailed the book, I had to cancel the order.  I sent a PM to the requester saying that once I found the book, I would be more than happy to send it to her.

Well, today I found it.  But I'm worried that if I post it on my bookshelf again, someone else might request it before she has a chance to.  Is there any way to avoid this or do I just have to reject any other claims that might come in before hers does?

Is it a book on Wishlist?  If so, you go to the other member's WL and use the "post this book" button on that page to post it directly to them.

If it's not, you can go to your Transaction Archive and find the request and then PM the member and let them know you've found the book and would like to repost it for them.  Once you cancelled the request, the system would have rolled the request over to the next person that had the book available.  If yours was the only copy, then the book should have gone onto the other member's Wishlist.