How to Find Old Yearbooks
Yearbooks are not the easiest thing to find since a school only orders enough for its students. Some people have found their old yearbooks on eBay and Craig's List, and others have found them through social networking. The direct approach is to go through the school itself or track down a former classmate who no longer wants his book.
Check online yearbook sources for an electronic copy. Sites such as old-yearbooks.com and classmates.com keep some copies of old yearbooks sorted by state. Some of the sites will require a free registration to see an entire book.
Visit the library at the high school. High schools often keep a copy of every year's annual yearbook. Most high school libraries are more than willing to allow alumni to visit the library, browse through old yearbooks, and make copies of the pictures. If you want to buy the book, you may be able to work out a deal with the school.
Contact the yearbook's original publisher and ask if they do yearbook reprints. Some yearbook publishers, such as Jostens, will reprint a yearbook. You'll need the written permission of the high school, which will also need to loan the book to the publisher. Expect this to be expensive.
See if the school has an alumni chapter. Contact the coordinator of that chapter and let that person know you are trying to find a yearbook. That will also put you on the mailing lists for reunions or other social events. Odds are you could meet someone at such an event who will have a book to sell.