For the code examples, have you tried looking up the home page for the
book? Â Google for 'oreilly learning python' and find the correct edition
that you have.
If its the 4th ed (current), you should end up on a page like this:
http://shop.oreilly.com/product/9780596158071.do
Down in the right hand side-bar, there should be a menu 'Essential
Links' and one of the options is 'Download code' or something along
those lines. Â The link should take you to a zip file with all the code
examples in the book.
As far as practice exercises... maybe something like
codingbat.com/python would be helpful. Â Its not related to the book at
all, and doesn't go nearly as in depth... but its kind of neat to play
with and see how your code works when someone else is grading it! (at
least for me).
HTH,
Monte