I use Lightwave, my personal preference. it's the daddy and its what they use on battlestar galactica so it shows it still can do it. 300 was made with lightwave as well.
go to
http://www.lwg3d.org/v3/index.php
http://www.scifi-meshes.com/forums/
two good forums.
CGtalk is another place to go.
then from there you need photoshop to do your texture work which in turn leads to a lot of sites for textures etc.
http://www.scifi3d.com/
has a lot of free meshes to start off. that's where both the y-wing and xwing came from although the xwing and ywing have been completely retextured by myself along with a number of detail changes.
50% of what you see is texture and model, 50% is down to good lighting and camera I personally think.