from what I read online, the windows easytether had to be heavily tweaked to get it to run on ubuntu... would really love if you shared how you did this :-)
Laptop running ubuntu and a droid X with grandfathered unlimited data plan._______________
My answer: I had no problems using EasyTether with Ubuntu 11.04, I down loaded both deb files from http://www.mobile-stream.
The i386 deb is the one that would load on my laptop, just start EasyTether on the phone, connected the USB cord between my HTC EVO and PC, then opened terminal in Ubuntu and typed easytether connect pressed return, and it worked, for me anyway. BTW, PdaNet doesn't have a driver for Ubuntu.