Ancestry.com has been offering some very good instructional videos on YouTube. On Monday a video was uploaded that gives some excellent searching tips by one of the staff members who works in that department. I listened to the video shown above, titled "Secrets to Searching Ancestry.com". Click on the photo to go to it.
One interesting point that I learned that I didn't already know was that when you do an "Advanced Search" and enter a death date for an individual, the only results that will show up will include that death date. That means NO CENSUS records would appear in the search results, since census records don't give death dates. The search results don't show what you already know about the person, they only give records that have the information in them that you entered in the search form.
You can learn this and many other valuable searching techniques by watching this video.