Google Search Cheat Sheet
Although search engines are constantly working to improve the quality of their searches, they seem to have no trouble increasing the quantity of what is being searched. Sometimes, it can help a great deal to steer the search more in the direction you need--Google might do a lot of various work in their labs, but mind-controlled search is still a few years off.
The Google Cheat Sheet is a 2-page PDF that clearly outlines many of the basics of Google. Very useful tips, and some quick shortcuts around the sprawling site.
Also useful -- IHackStuff.com has a Google Hack Database of many known searches that will yield "useful" results...