I cannot find a answer anywhere in the help docs...so, when you are looking at a book is there anyway to tell how many are available at that time.

If 500 copies are currently available, and if I post one I am going to be 501, I imagine that might take a while before the book goes out. I could use this info to keep my physical books in a better order.

Thanks.

put it on your wishlist, it shows how many copies are available

Put it on your Reminder List, not wish list.

It will tell you there how many are in the system.

No not your WL.  YOu cannot put an available book on your WL.  You need to put it on  your reminder list.

Reminder list...gotcha, thanks.

depends on the book.  I had several that were highly posted books that I never thought would move off my shelf, but were requested after only a few months.

I'm about to order one that shows 37 copies in the system; it's the first in a mystery series that looks interesting, but my library doesn't own a copy.

I'm mailing 1 out tomorrow with over 200 copies in the system. So they do get ordered. Granted I posted it about 6months ago but I have the book storage space. 

Supposedly they are working on a system to have it show on your bookshelf the rate at which a book is being requested.  Sometimes it's better to keep a book with 100+ copies in the system that's steadily requested over a book with 1 copy but never gets requested. 

If storage space is an issue you can also run a deal or join box of books to swap them out for books you haven't read yet.  Whenever my shelf gets built up with heavily posted books, I join box of books and usually have them all swapped out quickly.