Well, Amazon used to be ahead. I vividly remember using their "Find me this out-of-print book" service once and being very positively surprised that it actually worked. Signed up for the out-of-print book, got a message about 3 months later, and BANG, there it was, in my mailbox. That was one of the moment when I thought "well, they are really doing a great job" That has changed since, especially since the website design has been fucked up with ads everywhere.