Found some decent tutorials on YouTube... at the point when you have what you need just go to the 3D menu and "Export 3D layer" and that will give you the option to save as an .obj. 
You will also need 3DXchange to bring the obj into iClone ;)



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As Mark said, that is easy in Photoshop. If you have CS6 extended on up you can create a nice 3d object from a .png with it.
I did this rough test just the other day with this guy's signature, made a .png in Photoshop then converted it to an .obj, then brought it into iC7





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I keep forgetting I have C4D lite -- I should boot it up some time and take a look at it (I looked at it many years ago, but perhaps it would work as a tool for me at times).

Thanks for reminding me.

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Mike "ex-genius" Kelley

You can do it right in Photoshop.  A better way would be to 'trace' the PNG in Adobe Illustrator and export an SVG spline which you can extrude in Blender.  If you have the full Adobe Cloud Suite, you also have Cinema 4D Lite - so you can export a 'trace' from AE to C4D to extrude.

https://www.youtube.com/watch?v=rRdoBRR8V40