Heh. If my mod ever gets finished it'll have a sumptious manual (web-based probably) explaining everything. But then it's not scheduled for completion until 2009...
If you start a game with all the technology available (part of the Player Settings tab) you can click Help (somehwere in the top-left set of buttons) in-game and have a look. It's a bit of a spoiler and there aren't any long descriptions of what everything does and how. Some would say that's the fun of the game - there's always something you don't know/fully understand about the game.
As with all games, it's part of the learning curve to learn what's good to research and what isn't.
Re: Tech Tree with descriptions?
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