I was asked what online sources I use to find public domain works so I figured I'd write a post so everyone can have the list.
Library of Congress - The Library of Congress has two sources of digital materials you can access. Materials include books, videos, maps, images, handwritten documents, sheet music and much more. Check out Digital Collections & Programs (Library of Congress) and American Memory from the Library of Congress - Home Page to se ethe 100s of collections they have available for you to freely use.
Note: Most of the materials in the Library of Congress digital collections is in the public domain but some of it is not. Each collection has annotations to help you make this determination.
Archive.org - http://www.archive.org is a massive archive of books, film clips, movies, tv shows, music and other audio and software. There are millions of items available at archive.org but only a portion of them are in the public domain. The rest are posted under various creative license restrictions. You should read the license on a work. Many allow you to use them under certain conditions.
The Library of Economics and Liberty - Books | Library of Economics and Liberty is a great collection of books on economics and economic theory by the old masters.
The Online Books Page - The Online Books Page contains links to over 30,000 books in a variety of topics.
Self Help Books - free self help books online & free spiritual ebooks for prosperous living to download offers a small collection of self help books plus links to many additional repositories.
Ibiblio - ibiblio.org - Tibet a source of sources - offering links to many archives on the web in a large variety of topics.
Project Gutenberg - Free eBooks by Project Gutenberg offers more than 20000 books for you to use. Most of the books are classical fiction but there are some treasures buried in their pages.
The Free Library - News, Magazines, Newspapers, Journals, Reference Articles and Classic Books - Free Online Library offers a massive collection of books, articles and periodicals
International Children's Library - http://www.icdlbooks.org/books/index.html contains a massive number of children's books.
Internet Public Library - http://www.ipl.org/div/subject/browse/hum60.60.00/ offers a collection of links to a diverse set of literature in the public domain.
Remember - not all works in the above stated references are in the public domain. As with any material, you should conduct your own research to verify that the work is indeed in the public domain. (You can learn how to do this at U.S. Copyright Office)
Public Domain Search Entities
While knowing hundreds of places where you can find public domain materials is a great way to find more items than you can use in three lifetimes, there are times you need to find specific items. This section discusses various search specialized facilities that can help you locate that special public domain piece you need to complete your projects.
When I need to search for public domain materials, I always start with standard google searches and I'd say 8 out of 10 times I find what I'm looking for. But for those other two times, I rely on other specialized search locations to find what I need.
Here is a list of specialized search tools that you can use.
Lets start with google. Google is actually a large number of search engines. In addition to the default search engine, there are two others that I use on a regular basis to conduct my public domain searches.
The first is the google U.S. Government search at <Unclesam> - Google Search. Searching here will limit the results to just government entities. It is a great way to find public domain materials because almost everything that is returned is in the public domain. There is one caveat however. In addition to the federal government, it will return state and local government information as well. And since state and local government materials are probably copyrighted, you need to pay attention to the sources you are examining.
The second google search is the google book search at Google Books. This is an excellent source for finding books that are probably in the public domain. Using Google Books - Books Help will give you more details on what you can do with google's book search and its functions. A quick tip is to select "full view only" when doing your searches.
This returns only books you can read in their entirety online and many of them are public domain works. (As with any public domain work, you should do your own research to verify that this is the case.)
W3 Search Engines
While not a search engine, WWW-VL: W3 Search Engines - Internet search engines, website tools, Hilltop search engine, anti-spyware, web site SEO, search engine optimization, Laughead Web should be in everyone's public domain bookmarks folder. This page is like a who's who of search engines, technologies and search techniques. Invest a bit of time perusing the knowledge here and you will soon be a top notch search engine specialist - able to hunt down the most elusive bits of information quickly and easily.
Internet Public Library
The Internet Public Library is a huge compendium of links to sources of online books, many of which are in the public domain. ipl2: Information You Can Trust will get you there.
Twenty Public Domain Ebook Sites
20+ Places for Public Domain E-Books is a great jumping off point to twenty sources of public domain ebooks. It is a great starting point to find tons of already digitized and ready to use books covering a wide variety of topics.
Used Book Sites
There are two great sites that sell used and antiquarian books from a huge variety of booksellers all over the world. These sites allow you to find books from ancient times to modern and have a variety of search facilities that let you perform data range searches. This allows you to tell them to only return older books.
There is no guarantee that any books returned by these sites are in the public domain. You will need to research that fact yourself. And these are also all physical books so if you find a book you need for a project, you would need to get it into digital form yourself. But a lot of times you can find just the right book for your project at a surprisingly low price.
AbeBooks Official Site - New & Used Books, New & Used Textbooks, Rare & Out of Print Books and Alibris: Used Books, Used Textbooks, Rare & Out-of-Print Books. When using these sites, be sure to use the advanced search function so you can control the date range for the books returned to help limit the amount of searching you need to do through the returned listings.
U.S. Government Search/Portal Sites
Since most of what is available from the U.S. Government is in the public domain, it is good to know a few entry points into the vast maze of their online collections. Here are several that we use:
- The U.S. Government's Official Web Search
- Browse Topics
- Business.gov - Official Business Link to the U.S. Government
- USA.gov: The U.S. Government's Official Web Portal
- FedWorld.gov home
- GPO Access Home Page
Last but certainly not least is the World Public Library at World Public Library Association. It costs just $8.95 per year but offers a huge search archive. It is well worth the small investment
This list is nowhere close to a comprehensive list but I hope you all find it useful.