Solidworks, Catia, Autodesk, lots of great 3D modeling software. And it's getting easier and easier to use.
Like Ganef said, it's important if you ever want to be taken seriously. Those 'sketches', which is even a stretch by that term, mean absolutely squat. Couldn' even take the time to scan in your bar-napkin idea and took a picture of you holding it up instead? lol. That's nowhere near a "blueprint".