Jasper Fforde, whose books I adore, has some items for sale on his website.
Most of them are the standard sort of things, books, t-shirts, and so on.
And then there are the prints. I want, nay, NEED these. The fact that I have no room left on the library walls is completely and utterly immaterial–that’s what the guest bedroom is for!
(The dodo and the grammasite are my two favorites.)