The connection between Area 51 and Edwards North Base is pretty obvious given that the Janet planes fly from McCarran to North Base on a daily basis. The oldest reference to the Area 51 connection is on the UFOMIND website, which also provides documentation that the North Base runs the operation at Groom Lake. The history of the North Base is very rich, starting with the first American jet, the XP-59A. In the nomenclature of Edwards Air Force Base, North Base is also referred to as Operable Unit 10. Most of the information about North Base on the Edwards website is related to the toxic clean-up efforts of various flavors of rocket fuel. One of the more interesting links is about a special 3D thrust measurement system to be installed at North Base.
See the Janet page for recording of flights from McCarran to Edwards. In addition, you can monitor these flights yourself using a remote controlled radio located in Lancaster, Ca.
The North Base can be easily seen from highway 58. These photos were taken from a nearby hill (35.03703 -117.90178), and unfortunately the hill isn't nearly high enough to get a good view of the base. If you have the dvju plug-in installed, click here for a panoramic photograph of North Base.[Don't forget to use the "zoom" feature else you won't see a thing!]
The photo below is to give a perspective on the viewpoint relative to the terraserver satellite images. The center of the runway of North Base is 34.99051 -117.8639.