Web Sites/Pages:
Floppyshop are a long established and large public domain library, who have provided an excellent service to Atari owners over many years. The also supply commercial software products, such as Positive Image, EZ-Art Pro and Family Roots. Their site was developed by Frank Charlton of Tachyon Communications, and includes a run-down of their commercial products and PD/shareware catalogue.
LAPD's site contains the usual elements that can be expected from PD libraries. A company profile and news pages can be viewed, and you can download their Atari software catalogue. Interestingly though, the site also contains personal profiles of LAPD founders Clive and Leigh.