The American Presidency Project
"The only free online resource with a single searchable database including:
POTUS (Presidents Of The United States)
The Internet Public Library’s POTUS page has audio and video files, election information, historical documents and more, pertaining to all 43 presidents of the United States.
Compilation of Presidential Documents
Entries date back to 1992. Browse some of these things - you'll be amazed! (check out Bill Clinton's speech about minimum wage or George H. Bush's news conference with Boris Yeltsin in Tokyo)
President Trump's Twitter Archive
50,000 tweets and retweets, includes the realdonaldtrump account. This is searchable . You can search with commonly used words or phrases.
From government documents librarians, list of sites for presidency documents - some of these are also found elsewhere in this guide, but it's good to be able to find it in a myriad of places:
1) Documenting the Now catalog of twitter datasets:
2) End of Term Archive (we’re currently running the 2020 crawl of the .gov/.mil domain):
3) Internet Archive (lots of content, esp in the TV archive etc):
The MIller Center at the University of Virginia has collated Presidential recordings from the Roosevelt, Truman, Eisenhower, Kennedy, Johnson, and Nixon Presidencies. While the recordings themselves are only available to registered users, you can register for 48 hour use. There are also transcripts and context articles available.
For more information about the project, check the info at the National Archives Presidential Recordings Project.
Oh my, while we're at it - check out the Miller Center AMERICAN PRESIDENT site. Recordings, essays, images and so much more.