Of all of the various spellings of names that sound like my own surname (Coon) I have settled on about four out of about eighty that could probably be the real German spelling. They are Kuhn/Kuhns/Kuntz/Koontz. I am told that none of these German names are likely to start with a 'C'. That eliminates all of the Coontz/Coonts/Coon/Coons, etc. Also, two o's are pretty unlikely, eliminating the Coontz, Koonts, Koontz, Coonts, etc. As I look at histories and surnames around the country I see that Pennsylvania and Maryland seems to keep to the (I hope) more accurate spellings.
In the 1820 Federal Census of Fairfield County, OH my GGGGrandfather and his two brothers are listed as 'Koontz'. In the 1830 census and all later census' they are 'Coon'. My GGGGrandfather always listed as being from PA. Over the years the surname has been spelled many other ways including Cone, Koon, and Koons....simply spelled the way the English speaking official thought it should be spelled. The further west you go over time the more variety of spellings. Again, Pennsylvania seeming to remain mostly accurate in the Germanic spelling.
Mylelf and several other researchers experiencing this recordkeeping/spelling difficulty are using DNA research (with some success) to get past all of the records/spelling and find relationships among their lines. There is more information on a webpage at: http://www.familytreedna.com/public/coon If you can't join, you may want to check the results periodically to see if your Kuhn/Kuhns/Kuntz line is included. We've had several successes and look forward to more in the future.