Visit your local public library. Every library has a specially-trained reference librarian who can help you find the answer to most any question. If the reference librarian can't help, consider another library that might better meet your needs. For example, if you need answers about high-level chemistry experiments, try the science librarian at a major university. If you are in high school and need answers pertaining to a school project, check with your school media specialist. This person orders materials pertaining to the curriculum and has likely helped students in your situation.
Use encyclopedias. Many people run straight to the Internet for answers to their questions and neglect to question the authenticity of the answers they find. There are millions of websites out there, and sorting through them all to find a particular nugget of information can be very annoying. Often, trying the "old-fashioned" method of using a current encyclopedia can reveal more expedient, succinct answers.
Surf the Internet. Despite its above-mentioned flaws, the Internet is a wealth of information. Some sites, such as Yahoo! Answers, allow users to submit questions upon which the general public can comment.
Ask around. By utilizing your network of friends, relatives and acquaintances, chances are someone in your circle knows the answer to your question.