I'm searching for an API or a program (preferably Python and open-source) which lets me download the first n pictures of a Google Image Search for let's say bicycles. It would also be helpful if it could download the first n .pdf files from a normal search. Since not all pictures and .pdf files are found on Google and since there are many other search engines, a program which could also scrape results from Yahoo or Bing would be very convenient. Are there any such programs or is there an API from Google which lets me do more than 100 searches a day?
edit: People passing by may want to look at my attempt of programming such a scraper here