For content:
1. Search for stuff under creative commons copyright. They are usually free to use. Sometimes you just have to mention "Source: ______" after using the content.
http://search.creativecommons.org
2. You can use softwares that create games likes Sudoku and Crosswords. And paste these games on the newsletter.
3. You can probably joint venture with someone like Randy Cassingham. Pay him to allow you to syndicate his content. He publishes "This is True" and "Stella Awards" newsletters. Both are topics that masses love to read. And both are kind of timeless. I don't know how much Randy charges though...
4. You can also pay a fee to those syndicating companies like United Media. And publish comics and columns.