Michael J. Hammel's article “Linux and the PalmPilot”, which appeared in Linux Journal in June 1998, is old but discusses the use of pilot-xfer, which is still very useful. You can check it out at www.linuxjournal.com/article/2711.
The HOWTO document “Palm OS Desktop HOWTO” can be found at www.linuxdoc.org/HOWTO/PalmOS-HOWTO.html. Most of the links that contain “orbits.com” don't work anymore. Apparently this company stopped serving the mentioned HOWTO documents. If someone can find these lost documents, please send them to palm@duo.be, and we'll put them in our Palm directory at www.duo.be/palm.