This site claims to be
the world's first site to distribute original new puzzles every day.
They distribute three new problems every day out of five puzzles:
Sudoku, Edel, Kakro, Slither Link and Nurikabe. All of these puzzles
are available in Java and PDF versions and you can play many of them
for free as well.
A Japanese site on pencil-n-paper puzzles. Although some pages are in Japanese only, you can get there many "Paint by Numbers" puzzles in the Regular Puzzles section. They are displayed in PDF format, and updated every Thursday.