Are there any video tutorials or gameplay videos with commentary?

yes

videos with commentary, however not exactly tutorials:
official one from IC/stardock, these shows a few things like empire tree...etc.
both are 11 minutes long, one is from a older version of the game and two is something thats a version close enough to 1.02 (might be 1.01).
http://www.gamespot.com/video/935993/6182903/sins-of-a-solar-empire-official-movie-1
http://www.gamespot.com/video/935993/6185226/sins-of-a-solar-empire-official-movie-2

tutorial video:
non official one on youtube, I havent watched this, only stumbled upon it when going through sins videos.
http://youtube.com/watch?v=2C1-EdJ7MYg
the comments say its helpful.

Cool thanks