Add note on errata to readme

Author: amueller

Diff for: README.md

@@ -56,4 +56,10 @@ You also need to install the graphiz C-library, which is easiest using a package
 If you are using OS X and homebrew, you can ``brew install graphviz``. If you are on Ubuntu or debian, you can ``apt-get install graphviz``.
 Installing graphviz on Windows can be tricky and using conda / anaconda is recommended.
 
+## Errata
+
+If you have errata for the (e-)book, please submit them via the [O'Reilly Website](http://www.oreilly.com/catalog/errata.csp?isbn=0636920030515).
+You can submit fixed to the code as pull-requests here, but I'd appreciate it if you would also submit them there, as this repository doesn't hold the
+"master notebooks".
+
 ![cover](cover.jpg)