Welcome to RampCalc! RampCalc was written to help you design your mini-ramp using 4x8 sheets of plywood. Just enter dimensions and press Calculate. Enjoy!
If you're looking for a good CAD program try AutoCAD, IntelliCAD or SketchUp. I have used both AutoCAD and IntelliSense and both are great programs if you can afford them. SketchUp is a nice alternative to the higher priced CAD programs. SketchUp offers a student version for pretty cheap. I recommend downloading it and trying it out.