Did you know that the Newberry Library in Chicago has its own online research guides that can help you, sitting comfortably in your pajamas doing online genealogy?
On this page, you can find research guides--most available in downloadable .pdf format--for any genealogy topic under the sun, from Adoption Research to the World's Columbian Exposition, held in Chicago in 1893. There are research guides for 27 states and the Province of Ontario, as well as major city, regional, ethnic, and overseas resources.
When looking at the research guides, you won't find a how-to, but rather a list of resources for that topic that are held in the Newberry Library. How is this useful? Suppose you are researching ancestry in the state of Maine. The Maine Research Guide will give you a list of books and periodicals for which you could check your local library. If not available, use WorldCat to find the nearest library that holds these resources and use inter-library loan to peruse it at (or photocopy the pertinent article to be sent to) your local library. Some of the research guides, such as the one for New York State, also have hyperlinks to online resources. You may find a listed resource so useful that you will eventually want to purchase your own copy at your local bookstore or through Amazon!
This is an excellent example of the Internet being used as a finding aid, a research tool, to find genealogy resources offline (remember, not everything is on the Internet, and it never will be!). Happy Hunting!