To help illustrate the crawling examples we have created a sample website at http://example.webscraping.com. The source code used to generate this website is available at http://bitbucket.org/WebScrapingWithPython/website, which includes instructions how to host the website yourself if you prefer.
We decided to build a custom website for the examples instead of scraping live websites so we have full control over the environment. This provides us stability - live websites are updated more often than books and by the time you try a scraping example it may no longer work. Also a custom website allows us to craft examples that illustrate specific skills and avoid distractions. Finally a live website might not appreciate us using them to learn about web scraping and might then block our scrapers. Using our own custom website avoids these risks, however the skills learnt in these examples can certainly still be applied to live websites.