For the past year, I've also watched the reprap project (www.reprap.org) create a machine that starts with nothing but a roll of plastic filament and create THINGS. The reprap first generation machine was known as the "darwin" (~$1000), and the second generation is called the "mendel" ($800). An even simpler version of the mendel - the "prusa mendel" can now be constructed for <$600. By using the 3d printer to then print the parts needed for the next printer (reprap is an abbreviation for self-REPlicating RAPid prototyping maching), subsequent printers can be made for <$400.
The reprap is clearly the hard-core open-source hardware DIY option (although kits are available). A more commercialized version is available. Makerbot (www.makerbot.com) commercialized the reprap machines, first with the "cupcake" and now the "thing-o-matic". These 3d printers have laser-cut wood sides and are designed for easy portability. (Who doesn't want to borrow a 3d printer?!)
Other commercial options are available - the UP! printer (http://pp3dp.com/) is the most turn-key. You remove it from the box, plug it in and start printing. The Ultimaker (www.ultimaker.com) promises faster printing and a MUCH larger print area, but hasn't been released.
As you can tell, I'm all about the research right now. I'll use this space to store some links and my thoughts as I think through this adventure in learning. In the meantime, I think this video says it all...