The issue is really that solid surface is not very easy to DIY, which is part of the reason they won't usually sell it direct. The link to solidsurface above is good as I have bought scraps from them.
The edges are glued and then sanded/polished, etc. You will also generally want to use a router to get the edges rounded or whatever you end up wanting. Not outside the realm of DIY but you'd need to have fairly decent skills.
Any local kitchen installer is going to want to measure themselves and do the install, you probably wouldn't save much having them fabricate the counters and installing them yourself.
How extensive is your project? Any complications like 45 degree angles and such? What type of backsplash do you want? Tile on the wall or do you want the corian to have it's own builtin backsplash?
