I could be thinking too complicated, but either way I thought that I should share.
Well, my first thought was Rhinoceros, which is a 3D software (for windows)
With it you can quite easily make 3d text and basic 3d objects like cubes, cylinders and stuff..
Furthermore what I had in my mind was the Make2D feature. It allows you to make 2d drawings out of 3d objects..
You can then save those lines in .ai format.
Here's an example of (not 100% accurate) iphone that I have made (long ago) that I now converted to lines and from that brought to Illustrator.
If what you want is to fill it with color.. that maybemay be a bit tedious work as you need to join paths before you can fill it.. Select 2 or more lines and Ctrl+J.