this was magetesting.com
some sparse, neglected and likely outdated info is here on the Rocket Web wiki: https://wiki.rocketweb.com/display/MT/Mage+Testing+Walkthrough
Mage Testing is licensed under the "Don't be a Jerk" license.
Rocket Web poured a ton of effort into this over the years but we're not going to use it anymore. So enjoy this, use it, make something new from it. But if you use this commercially, you owe Rocket Web some recognition.