You mean to say you actually
designed your ships?
just kidding!
As for your question, well, right now you can't buy SEIV IIRC - you'll have to wait until Strategy First starts selling them. However, there might be stray SEIV or even SEIV Gold CDs on sites like Ebay.
I've played the GalCiv1 demo once and lemme tell you one thing, that set the record for the game that survived longest on my HD! That game just
sucked..... A counter-intuitive research screen, a mysteriousness about ship construction, bad GUI - in fact, the only
good thing about it was that you had to research Universal Translator to be able to communicate with other races - but since you could only play as humans, that pro was pretty much negated.
SEIV:
-Is great for modding. You can make it into anything you like.
-Has got an excellent online community.
-Can be learned in just fifteen minutes but you keep discovering more and more strategies as you play the game (and talk on the forums).
-Comes with a slew of great mods. (Well, SEIV Deluxe will be - Strategy First is going to release (or so I've heard) SEIV Gold with multiple much-played mods, including but not limited to the Star Trek Mod, Adamant Mod, Pirates & Nomads etc.)
Need I say more?