There are some books I own that I'd be more than happy to lend out, but I'd like them back. So I was thinking when we send them out, why not include with the book a self addressed, stamped return envelope?
Book rate is very reasonable, if you want to wait a little longer for a book to arrive, and priority mail is not all that much more.
Just a thought :)
Also-- Should we list what we have and are willing to trade? Those entries could be placed in "memories" for perusal of everyone in the group, similar to package gang with their surveys.