Do not search for an exhaustive list of links to Palm programming sites. Others have done it much better than I could have done it myself. But, are listed here my favorite links.
I just have to start this list with the PalmPilot Software Development - Alternatives to C page written by Michael Winikoff. . This is the ultimate reference of a listing of all development tools available for the Palm OS platform. New as of July 2008: Michael Winikoff decided to stop maintaining this page and he kindly offered me to host it.
Another very good site is the one of the Palm Gaulois.
The site where French developpers (known to be among the best in the world) would meet and share was PeekPocket. This site has unfortunately closed.
HSPascal is a great shareware Pascal compiler for Palm running on a Windows PC.
Palm OS Pascal Compiler, nicknamed "PP", is a great freeware Pascal compiler for Palm running onboard of Palm devices.
I was a very early adopter of PP when its development was just starting. So, I kindly invite you to: