Help with OpenFoam

I'm new to CFD and I need to run a study on a vertical axis windmill I'm developing. I have a cad file (step) and I can't figure out how to import it to FoamX. I've read the user guide and the programmers guide, I've also looked at the forums for CAE Linux and Open FOAM. I'm using CAE Linux 2008, the latest 32 bit version. I'm thinking Turbfoam for the solver. The highest velocity will be 20 m/s and the model is 1 m in diameter with no symmetry. So I'm basically looking at incompressible, turbulent flow of air. I'm not an engineer either so I have no way of estimating how long it will take to comverge for torque, probably 6-700 n/m(Z axis) and drag probably 40 - 50 newtons (normal to Z axis). I also don't need really good accuracy, within 10% would be plenty good. This is for a wind tunnel model I'm going to build and test. Thanks in advance. Bill