[Ruatha]

The best way to view the tech tree imo is by using the two excellent programs that can be found in this forum.
SE4Mod utility (make a search or check the newbie faq for links) and the "techtreeviewer" a java program (make a search in this forum).
Otherwise you have the text files in you SE4 Gold DATA subdirectory, ie TechArea.txt, facilities.txt, components.txt

I like SE4mod utility best.