Here's why:
* The books are collections of anonymous submissions. The essence of Post Secret is that people send in their secrets anonymously. Selling a book with those secrets would potentially violate the privacy of the people who submitted them.
* The project is ongoing. Post Secret is a continuous project, with new secrets being submitted regularly. A "book" would be a snapshot in time and quickly become outdated.
What you *can* do:
* Visit the Post Secret website: The official Post Secret website (postsecret.com) has a large archive of secrets, many of which are organized by theme. You can browse these online.
* Buy merchandise: The website also sells merchandise, such as t-shirts, posters, and mugs, featuring some of the secrets.
* Look for limited edition publications: Post Secret has released occasional limited-edition books or collections, often focused on specific themes or events. These are harder to find, but may be available through online marketplaces or used booksellers.
It's worth noting that you can find many "Post Secret" inspired books or articles online. However, these are not official publications and may not be representative of the actual project.