The Github repository containing these notebooks is https://github.com/clawpack/riemann_book.
You can view html versions of some of these notebooks at http://www.clawpack.org/riemann_book/html/Index.html.
Parts I and II of these notebooks will also be published by SIAM as a paperback book, and these are listed in Index.html. The ones listed below are additional notebooks that cover more advanced topics and/or additional hyperbolic systems.