This is a really good video showing how to use OutWit a simple to use Web Scraper that sits as an extension to Firefox.
Remember, there are ethical considerations about using Web Scrapers. In particular
- Some services have Terms and Conditions that prohibit automation, for example Google does.
- When deciding whether something is truly in the public domain it is important to keep in mind the author's intent. If somebody posts a comment in on online discussion they might have the expectation that it would only be read by human, not scraped and searched.
However, if the web scraper is simply being used to change 20 minutes of cut and paste into 1 minute of scrape and post, then there is probably not a major difference.