1. Find a logo image, preferably an eps.
2. Open in Adobe Illustrator.
3. Delete the part of the image you don't want.
4. Select logo text.
5. Set fill to none and stroke to none.
6. Select Object, Path, Simplify. Check box next to straight lines. Threshold angle stays at 0 degrees. Click Ok.
I know that using straight lines may look rough, but unless the logo you are making is huge (bigger than 6-10 inches) it will still look great.
7. Export to dxf, select location and enter file name.
8. On the DXF/DWG Export Options, Version 2004/2005/2006. Scale 1 mm = 1 Unit. Do not scale lineweights. True color, PNG.
9. Only thing checked under options is Preserve Appearance.
10. Click Ok.
11. Open your newly exported file in AutoCad.
12. Delete anything extra that may have been generated. For me there was a small group of arcs off to the left that were polylines.
Eliminate them. They will make the file unusable.
13. What you should have in front of you now is a block of a text/shape outline. All you need to do is select all of it, type "explode" and hit enter.
14. Save the file. You should now be able to use this DXF on a CNC Mill to engrave.
The programs I used were Adobe Illustrator CS6 and Autocad 2012. And an internet browser to find the image.
Good Luck,
Scott