Many of my student, well - I guess - almost all of us, use Google a number of times each day. Eventhough we use Google at a regular basis, many people actually are quite unfamiliar with the tips'n'tricks of this great search engine.
I used, well .. Google, to find a couple of articles about optimized searching - and without furher ado - here's the top 3 articles I found:
http://blog.outer-court.com/archive/2005-09-29-n85.html
http://www.googleguide.com/advanced_operators_1.html
http://www.pcmag.com/article2/0,4149,1306756,00.asp