I have a Party Zone with fragile ramps that have never been reproduced so I've had similar thoughts. Experimenting with 3D printing, I've made some 3D models in FreeCAD; they weren't too hard to create once I got a little knowledge of the software. I used 3DHubs.com to get what I designed printed locally... a neat idea but I was generally unhappy with the product results. Most of the 3D printers people have today are essentially tiny-nozzled hot melt glue guns - they couldn't produce the precision I needed for the small parts I tried to print (parts were less than an inch in each direction). There are better printing methods out there (i.e., shapeways.com) but I haven't progressed beyond the 3DHubs point.
For ramp replacement the precision probably isn't as important as it was for my project, but you need a printer with a large build volume... and that is not what you typically find by default. I'm sure there are plenty of hurdles, but the best way to cross them is to take them on one at a time. So, download the software and get started!
-Rob
-visit http://www.kahr.us to get my daughterboard that helps fix WPC pinball resets or for my Pin2K H+V sync combiner