Picked up GC3, I really like it, but I'm also seemingly really bad at it.  

I can NOT figure out how to do well in this game.  No matter what I try, my pathetic little civilzation becomes the laughing stock of the galaxy and I've flushed another three hours down the drain.

How do the computer players do it?  What can I do to advance as fast as they do?  What are some basic strategies to at least get on even footing with the computer fairly early on? 

For the record, I've several different approaches, Research heavy, Building heavy, etc., but it always ends up the same.  The computer quickly has double my tech advances and is fielding warships I can't even damage.  AAARRrrgghhhhh!!!!