Specifically, I have a Garmin Forerunner 305 (a GPS-enabled, hear-rate-monitor for runners). I plug it in to the USB port and it is not recognized by Ubuntu at all. I'd like to be able to have it recognized, so that I can pull the exercise record from the watch. This would allow me to upload it to the Garmin Connect website, or perhaps use a Linux exercise software option. I'd also appreciate suggestions for exercise software to use with the Garmin.
I can highly recommend trying Linux Garmin Communicator Plugin. This is a "native" ubuntu solution and there is a ppa repository.
Having just got an Edge 500, I installed this plugin on Natty and it worked fine with Chrome and Firefox. The Garmin Connect upload button finds the device and uploads activities as requested.
I am also looking for a good pure Linux answer to this. I've owned a Garmin Edge 305 for 2 years and have been a full time Ubuntu user for 3-4 years. This is (sadly) how I do it:
Install VirtualBox, then create a windows virtual machine. From there it's pretty straightforward. Install your favorite drivers and software for dealing with your training data and use it from there. (This question has a bit more on the install step if you haven't used VirtualBox at all)
Some caveats: Once you have booted into your virtual machine and selected the Garmin device from the USD devices drop down to 'plug into' the virtual machine (shows up as an 'unknown device' for me), the Garim will not immediately work. It will show up in the device manager, at this point you need to disable it and re-enable it, then you are good to go.
Clearly this isn't a pure Ubuntu solution, but given my software of choice doesn't work under linux yet, I didn't have much choice. (Zone 5's SportTracks, though supposedly they are getting close to running under Mono) There are other solutions, but this has basically been the most efficient way to deal with training data from a Garmin I've found.