I'm also thinking about trying to speedrun factorio in the near future, personally I'm going for the boneheaded approach and I'm designing some software to create and optimize a new build strategy, as that's an aspect I find interesting. Perhaps I will manage to finish that work in the next few weeks :)

After watching a few (maybe, many) recent AnitElitz streams, I can probably recreate his current build pattern from memory.. And that's certainly a good way to get started. Maybe screencap the stream at various points and use that as reference. Or try building them out in creative, so you understand all the placement, and capture that. This isn't exactly a big time investment, compared to each run being ~4 hours, probably far more at first. I don't think his strategy is perfect but has a lot of neat qualities. Once you start playing around with it, you'll probably have some ideas on how to do it better.

As far as the tracking tools, I'm pretty sure Anti + most others are using LiveSplit