Regarding "how and why" to search the Internet, a major part of my job as a professional reference librarian is to know both where and how to look. This is the first thing I was taught at library school.
It first depends on what information you need.
If you are doing the ubiquitous "Indians of Texas" assignment (a real favorite of fourth and seventh grade teachers in Texas), you need information on how specific Native American tribes lived before the Europeans (white men such as Cabeza de Vaca) showed up.
I have several excellent reference books which I have been relying on for years which give the information teachers want the students to find on the Karankawa, the Jumanos, the Lipan Apaches, the Kiowa, the Comanches,etc.
If, however, you want to know how the Comanches are faring today and perhaps are interested in why museums all over the United States are currently in the process of cataloging Native American remains preparatory to returning said remains to their respective tribes, then this is a current, even a breaking story. Clif and I have several excellent Native American web sites that have lots of information such as this.
We also get a lot of demand at my library regarding the "dinosaur" assignment. Again, I have entire encyclopedias (one-volume but full of just the right information for a good school report) devoted to dinosaurs. If, on the other hand, you want to know more about the Utahraptor (a relatively recently discovered dinosaur), the Internet is a good source as well as popular magazines such as Discover, Scientific American, etc.
My rule of thumb is that I remember when books and magazine articles first began to be available on computers online, cd-roms, etc. This was in the mid-1980's. So, if I'm looking for something that primarily occurred or began to have a lot written about it in the last ten years, online sources such as the Internet might be a good bet. I do use the online subscription magazine index at my library fairly heavily, too.
I try to tell students when we do tours that if they can't find the information which they need in twenty minutes or so at my library to please ask myself or one of the other reference librarians on duty. I had another student tonight who said that she had already used the online subscription magazine index computer but it didn't have anything on her topic which happened to be heliotherapy (the use of light to counteract mental depression). I got on the computer and, instead of asking for "heliotherapy" I asked for light on the first line and depression on the second line. I got back almost two dozen hits. At least one had been indexed under "phototherapy". The student and her mother were amazed at how many articles I retrieved that were on her topic but had not been indexed as she had expected.
Public librarians don't bite! Please, do ask us. We are available to answer questions by phone as well as walk-in.
(By the way, I've tried to add URLs to the Free Internet Encyclopedia for the topics which I get asked most frequently at the library. As we go along, more and more of the kinds of questions I answer every day will be answerable through our encyclopedia. At least, that's my goal and my hope.)
The most important thing to ask yourself if you are not retrieving usable hits whether searching the Internet, your online public library catalog, an online or cd-rom magazine (frequently now including full-text articles), is "Is there another way to approach this topic?". I had a man today whose wife may be facing problems at work with an employee she supervises who may have religious objections to work on Saturdays (for instance). Instead of searching only for employer's legal rights regarding religious privileges at work I looked for employee legal rights regarding religious questions in the workplace and found several additional resources.
The Internet will not always be the answer. It doesn't have the general information found in a good public library. But it has its role, too.
Thanks so much for checking us out. I hope that our encyclopedia will prove helpful to you in the future, as well!