ResearchBuzz.org shares how to go about ‘turning Google into a near real-time search engine’.  Near real-time are the key words here!  Want to know what was indexed mere ’seconds ago’ about ‘libraries’ find out:
http://www.google.com/search?q=libraries&tbs=qdr:n

Other options such as a ‘day’, an ‘hour’, or a ‘minute’ can be found in the post on Research Buzz.  Check it out!