Step 1: Photoshop!
Step 2: Solidworks!
I've been using the program for a while so I find it pretty intuitive but it's really hard for a first timer. If you've never heard of it you might consider trying simpler programs like VectorWorks, Blender, or Google Sketchup before hunting around for SolidWorks. That being said SolidWorks is what I've got and what I know so it's what I used.
I started by importing my drawing on the top plane with insert>dxf/dwg. Then I created a new sketch on that drawing and traced over the shapes with the sketch tools. From there it was just a few simple cuts and extrusions to create the logo in 3d. Now all I had to do was scale it down to the right size and save it out as an STL (a common 3d format to deliver to the CAM program.)