I was recently noodling around on the Internet, looking at pictures of old bookbinding styles for inspiration in making my books, when I ran across a University of Iowa website that has pictures of reproductions of old books, including early codex bindings, stationer's account bindings, and medieval monastic bindings. Here is an example of an account book that uses a binding style that was common in the 9th-14th centuries.
Being a bit of a book junkie, I was immediately interested. I like how they include information about the time period of the binding style. Also, original books are often in pretty bad condition, so it's interesting to see modern versions of old bindings, to see how they might have looked when they were new.
Here is a picture of three books I just finished that have medieval-style bindings (the same ones I have pictured in my previous post) . They are all limp leather bindings. For the books on the left and the right, I used a longstitch/linkstitch binding, and the middle one is a different variation on a longstitch binding. If you look carefully at both pictures, you can see that the one above (from the University of Iowa site) is also a longstitch binding. There are many variations on the longstitch binding, which, for me, is what makes them so interesting to do.
Update: here is a link to the U of Iowa site, which I forgot to include :/