The boneyard tour must be scheduled in advance, I believe at least 2 weeks. We tried to go last week, and were told that a security check must be done on anyone going on the boneyard tour.
We stayed in the Butterfield RV Resort and Observatory in Benson, AZ. Benson is about a 40 minute drive southeast of Tucson. It is also about a half an hour drive from Tombstone, and a little over an hour from Bisbee.
Tombstone is a great place to spend a couple of hours. Lots of shops, restaurants, and some historical sites.
Bisbee was very enjoyable. It is a quirky town, and has a large number of artists living there.
The Butterfield RV Resort is a very nicely appointed and well maintained RV park. The sites have paved parking for your rv, they are pet friendly, with two dog runs, and the observatory is free for guests. My DW and I were very impressed with the presentation at the observatory.
Whatever you decide, I think you'll find the area pretty cool and enjoyable.