How can I scrape data from the web into drupal?
Not to put a damper on things (I've written more scrapers than I care to remember and it's always fun), but such an act is specifically against Google's Terms of Service:


  Do not misuse our Services, for example, do not interfere with our Services or try to access them using a method other than the interface and the instructions that we provide.


I'm sure you'll be ok if you're doing this for fun/educational purposes (don't take my word for it though, I'm not a lawyer!), but if you make something commercial out of this you could find yourself in a tricky position.