the question will come up, what are you using it for? I went uber-cheap on my M100, as I dont use it for anythng but datalogging. For my personal PDA I have a HP Ipaq Pocket PC. If you plan on using the palm as a palm AND a logger, you might want a better one than I have. But that is if you plan on using ita as a Palm.
here is the ADL Plug to serial plug
Here is the Serial To Palm cable
Hope this helps.
Mike