Checking out the eThreads code via arch is very simple. First, though, you'll need to download a copy of Arch from the GNU site and install it on your computer. Once that's done, checking out the latest code is as simple as running two commands:
tla register-archive e@ethreads.com--public \ http://arch.ethreads.com/arch/ tla get e@ethreads.com--public/eTevolution--dev--2.0