Newspaper articles and obituaries are good sources for finding background information about an individual. Articles written about individuals will provide details about their lives, whereas obituaries will list helpful biographical information, such as: birth date and birth place; names of spouses, children, parents, siblings, etc.; education; careers; life interests and hobbies; and more. Sometimes the obituary includes a photograph. Depending upon the year of death, there may still be living relatives that could be contacted, but discuss this option first with your professor to make sure it is an appropriate approach.
Below are links to current and historic newspapers, as well as a link to the Denver Public Library's index to obituaries in the Denver Post and Rocky Mountain News. The DU Libraries has the complete run of the Denver Post online (1894-present), but not the Rocky Mountain News (1990-2009). If your obituary isn't in the online Rocky Mountain News, you can request it via Interlibrary Loan.
Searching the open web may also retrieve other types of documents, such as high school yearbook pictures. If you know which college the individual attended, that university may have digitized their school newspapers and yearbooks.