Ok - a stupid question from a newbie. How can I see a list of all books that I have sent? At some point after using this site for a while, I would guess that my list of books sent my be could be rather large. My memory is not good enough to remember which books I have read and sent on.

Go to your Transaction archive. From there you can adjust it to sort by books sent or to just show the number.

You can also use the Books I've Read list to keep track of books you've swapped here.  The BIR list has buttons for reviewing books, suggesting them to other members, leaving notes for yourself, tagging.  It even indicates which books you've read are Wish Listed, and whether or not they're set to auto-request, which helps make turning the books you've read into credits a snap :)