1. Think before you search

Take a moment to figure out what it is you are searching for, try making a list of potential search terms before you start. Also, consider if there is a logical place to start your research, it may be a search engine, but it may be somewhere else such as your school library web page. Also, figure out how you are going to keep track of your chosen sources before you begin your research, this will help you avoid plagiarism.
Read “Starting an Online Research Project” for more tips to get started.

2. Try several search engines, not just one

And start with the search engine that makes the most sense for your search.

Although major commercial search engines often return similar results, they work differently enough that you should use several search engines for every research project to help you uncover different resources.

Specialty search engines often search a specific group of web sites, or use different methods to search the web, specialty search engines will almost always generate better and more targeted search results in particular categories.

More on choosing a search engine:

findingDulcinea: Choosing a Search Engine

Choose the Best Search for Your Information Need

3. Make the search engines work for you

If you just type a few words or a phrase in a search box, you are not using all of the capabilities of the search engine to find the information you are looking for.  On most search engines, you can narrow your search by using common words like AND, OR, NOT, or by using quote marks to show you are looking for an exact phrase. There are more tips for using search engines more effectively in the article below.

Make Search Engines Work for You: Tips for Better Searches

Also, many search engines have advanced features or special usage tips that allow you to further refine your results. Here are a few examples of advanced search tips for common search engines:

Google search basics: More search help

More from Google

Bing Help

About Ask.com: Advanced Search Tips

4.  Dig Deep, the best results are not always at the top

And click on more than one result while you are at it. The focus of your search should be finding the best information available, rather than picking the first site listed on a search results page. Some Web sites are very good at making their content rank high in search engines, for reasons that have nothing to do with the quality of their content.  Thus, results near the top of a search results page may not be useful, while the research gems that will make your report great may be buried 4-5 pages deep.  So dig deep!

And when you start clicking on the sites, use these next few tips to help you decide which are the real gems.

5. Are you looking at a primary source? Why not?

The best research sources you can find online will be primary sources. With primary sources, you won’t have to worry about information getting distorted from one interpretation or another.

Here are some tips for finding primary sources.

Discovering Primary Source Material

And, since not all of your material will be primary source material, at least use the tips below to help you find out if you are looking at the original publisher of an article or an online copycat.

Finding the Real Source of Your Source

6.  Who created the Web site? Why?

When you do click on a web site from a search result page, take a good look at the web site as a whole to determine if it is worthy of trust. Instead of just reading the page or article you landed on, click around, revisit the home page and the about us page to determine what the site is really about. Is the site trying to sell you something? Does the site appear to have any social or political biases? Any of these factors can impact what information the site does and does not provide, and whether that information contains an unfair bias or a well-rounded overview of a topic.

For a more detailed look at evaluating Web sites, read on:

The Internet Detective offers “The Good, The Bad and The Ugly," covering online hoaxes, spoofs, scams and some common ways to spot them, along with a few real-world examples.

UC Berkeley Library offers a slightly more advanced guide to evaluating Web sites.

7. Are the ads on the site clearly labeled, or are they masked as information?

Many credible Web sites contain advertisements, but when the ads begin to be mixed in with the site content, you may find that the content is not trustworthy.  Just as an infomercial on television is an advertisement disguised as information, some web sites create content that is only intended to sell a product.

8. The author matters, who is he/she?

Once you’ve determined that the web site you are visiting is worth inclusion in your research, return to the specific article or page you were taken to by the search engine. Take a look at the specific author of the page you're reading. Especially on a site with user-created content, the quality of the content can vary a great deal. Ask yourself: What are the author’s credentials?

Use a search engine to search the author's name, along with key subject words, to find other work the author has published or third-party opinions of his or her work.

9.  The date matters, when was the article written?

Many Web pages indicate when they were created and last revised. Check the bottom of the page for a copyright date or look for a date near the byline of an article. Without a date, the current validity of the information is difficult to evaluate. Not convinced that date is important, read the article below to see what can happen if you disregard the importance of date.

Searching for Credible Sources: Why Date Matters 

10. Take a skeptical approach, and verify everything before you use it in your work

Anyone can publish anything on the Internet, cheaply and quickly. When evaluating information you find online, you must be skeptical at all times. The focus of your search should be finding credible information, rather than finding what you want to hear. And always verify information by confirming it with multiple sources. If you find a few unrelated, credible Web sites in agreement on an issue, your research may be done. The same cannot be said if you read something just once.