1.  The easiest way is just to talk to them in Diplomacy and look at what techs they have.  It's..probably too easy right now.  The other way is to look at their planets and fleets and see what they're building.  You can put a lot of sensors on a ship and get a good view.

2. Not currently.  I'm not sure when that is coming, but I don't think it will be here by the release. Patch or expansion? I don't know.

3. Things are changing so much in Beta that it's hard to commit to writing a guide about things that will soon be outdated.  For now, my advice would be to load up on beam weapons, make sure to extend their range with tech specializations, and...win.  Beta 5 will hopefully have new combat calculations that allow for more complex strategy.