Do you know Bookfinder and AddALL?

Recently I have been researching a collection of vintage and antique books on a topic I am not so familiar with - drama and plays - a number of which still retain their original dustjackets, so this has been a very fun endeaver for me!  (to view, click here)  I've been relying heavily on what I find by searching both http://www.bookfinder.com/ and http://www.addall.com/.

Bookfinder advertises itself in one instance with the quote "If they can't find it, it was never printed" and for the most part I'd agree...apparently my collection is so esoteric that select volumes have been forgotten by even the experts!

Both sites allow you to search by author and title as well as select further search terms such as used, first edition, hardcover, etc., and AddALL has a separate search specifically set up for Out of Print Books. 

When selling books I highly recommend using AddALL and Bookfinder to research what price others have put on the book, are there a number of the same book out there and what condition are they in, who is selling, etc.  This is an excellent way to research the current marketplace, something I consider essential when doing business.  By using both of these sites together, I have a plethora of information about a particular book for sale at my fingertips.

I encourage you to try out both of these resources, whether you happen to be in the market for a book or marketing a book to sell!

Enjoy and be grateful...