Does anyone know the "fictional" state, town, and street address of the Nelsons?

I have always assumed that it was in California. In one Christmas Episode they were out caroling in their shirtsleeves!A town was never mentioned I don't think! Just like Ozzie's occupation! What was it?

The Nelsons lived in
Hillsdale at 822 Sycamore Road.

Does anyone remember the episode where Joe Carlson goes on a business trip and Clara's friend visit's her in town...and thinks Ozzie is Joe because Clara is too embarassed to admit that Joe is on the business trip...a.k.a. "Coffee Ozzie"...I am dying to get a copy of this episode...it is in color, and the boys (David and Rick) are older and married...PLEASE E-MAIL ME!!!!