You would need a smart phone anyway to get the live tracking feature of the garmin to work. And smart phones, while super awesome, are also #@&#$ expensive monthly. But they're awesome.

Get a used garmin 500 or something and just upload your rides to the web when you're done. Then email your family the link. Now that the 510 and 810 are out, that would be reasonably inexpensive (I think). The bare unit was $250 new, I reckon you can find them for half that, and no monthly contract to fuss with.