Getting tired of the chip truck?
The big hub for the post office in your neck of the woods, off industrial blvd in W Sacramento. I actually go to tour it for a field trip when I was in Elementary school. As you crawl in frequent traffic jam at the Hwy50/I80 merge just before the Yolo Causeway you can see it to your south.
Matheson does postal work all over the left coast
http://www.mathesonpostal.com/index.php?page=Locations
Here in Reno I sometimes see the FLDs in Postal livery being used in the LTL operation.