I would first suggest doing it manually, then copy to a python snippet... see details here
Using the Results window—Help | ArcGIS for Desktop
You may be working harder than you need to:
Use Spatial Join—Help | ArcGIS for Desktop to get a count of your wells in each county
And then use it again(the other way around) to create a table with wells and county names, then you can Add Join—Help | ArcGIS for Desktop to your wells then use Calculate Field—Help | ArcGIS for Desktop to populate your field with county.
Retrieving data ...