it looks like PCA Graphics have updated their website to include pictures of the work they did... Including SCII!
I see nothing on that page that wasn't there in 1997.
then i guess i am just 9 years late but it's still pretty neat to know they have the original FMV sequences and plus that theres some bits that haven't made it to the final cut
These pictures are what I saw in a magazine a while back (I think Computer Graphics World - but I have no idea of the date or issue). I mentioned it in my thread about the "Flagship Schematic". Pretty good pictures, I'm going to drop them a line to see if they have higher resolution versions available.
George Barr has some slightly higher resolution versions of the paintings he did for the aliens and cut scenes on his site at http://www.well-of-dreams.com/thingamajig/. I'm late to the party too - recreation of ships in Star Control II seems to have peaked several years ago, and SC3D seems to be the biggest remnant of it. (Unlike, say, the B5 modeling community, which seems to still exist.)