Wikipedia has a page for Stoutenburg, California. There is not much information on the page but it did reference page 808 of a book. In 1998, David L. Durham authored a book, California's Geographic Names: A Gazetteer of Historic and Modern Names of the State.
Apparently Stoutenburg was a settlement during the California gold rush near Murphys, California on Coyote Creek. Wikipedia claims that the settlement was named for a German gold miner. Mr. Durham may have gotten his information about this settlement from an article published in 1927 in The Concord Society Historical Bulletin No. 6. The Article written by Erwin G. Gudde was entitled, German Pioneers in Early California. Dr. Gudde was an assistant professor of German at the University of California in 1927.
He wrote on page 16, the following:
The German gold seekers, moderate and industrious, formed a large percentage of these and established a number of mining camps, among which were Stoutenburg, Mosquito Gulch, and Dutch Flat.I doubt that it was named for a German Stoutenburg. I have seen many instances in which Stoutenburg is seen as having German origin. Even people who are named Stoutenburg but no little about the name often believe it to be of German origin. The name is derived from a Dutch city in the Utrecht Province.
Since I do know that Stoutenburgs were in California during the gold rush, the settlement was probably named for a man named Stoutenburg and who was a miner.
So where was this settlement?
Calaveras County is one of the counties in California on the western side of the Sierra Nevada mountain range in which gold was mined. According to the book, Stoutenburg was located on Coyote Creek west of Murphys. Looking at satellite images and maps, I was able to find Coyote Creek.
It runs through or near the towns or villages of Douglas Flat and Vallecito on its way to the New Melones Lake. Although I have not been able to pinpoint the location of Stoutenburg, it was probably somewhere near Douglas Flat. Coyote Creek originates east and south of Murphys.