Man there's not a lot to write in a readme for such a book.
You can get the license info in LICENSE.TXT (hint: it's the MIT license).
I probably won't copy it in every module. Just pretend it's there, please.
The code in these files has been tested with Erlang releases R13B+. In case you're not sure it will run on another version, you can run the tests yourself by compiling tester.erl and then calling:
Which should run all the tests. If you're using the release R13B, there is a patch you need to apply in order to have unit tests running (see http://erlang.org/download.html).
Note that even if the tests run fine, you'd benefit in using releases R13B+.
If you need any more help, don't hesitate contacting me: firstname.lastname@example.org.