Sites such as This Old Yearbook offer old yearbooks for sale. Classmates hosts a huge number of yearbooks on its site. The yearbooks on Classmates are typically not available for purchase, but they are fully searchable and allow users to download and print photos.
When buying the old yearbook is not important, the actual school that issued the yearbook is often a valuable resource. Most schools retain at least one copy of their yearbooks every year. While these yearbooks are not available for purchase, most schools allow photocopies. However, viewing yearbooks at a school typically requires making arrangements with the school administration, as these libraries are not open to the public.