With an interest in most things mechanical and DIY, I could not help but be intrigued when I found out about a former KickStarter project MakerSlide. This project allowed for a very low cost, highly reproducible means of creating linear bearings for extruded aluminum projects. Though I suspect you could adapt the open source plans to any solid material. The permanent website has more information: http://www.makerslide.com/.
Rather than having to produce the parts yourself you can just go to the MakerSlide store http://store.makerslide.com/ and purchase the components directly. I also recommend checking out http://www.buildlog.net to see the projects that others have made, most with the MakerSlide components.