As an avid book reader and public library user, I often find myself searching for the next book to borrow from my library. Typically, I start at Amazon.com with bestsellers or books I have read in the past. Then I use Amazon's "customers who bought this also bought..." feature to find similar books. As I browse Amazon.com, I keep switching to my library's website until a match is made between a book's interestingness and its availability in my library. The process works, but is tiresome... and although tools exist to facilitate library lookups (e.g. WorldCat and BookMarklets), I have been unable to find anything that offers an integrated experience. At minimum, existing library lookup tools assume you know what you want. E41ST attempts to fill this gap.