I would support davidsoffice view....Marana is very tight on security and you will only have very limited views from outside...and they certainly wont let you in. If you are flying your own aircraft you may be able do a touch and go, or just fly over, to get a good view of what is there. Mojave still do airside tours, but its now strictly no photography. In terms of quantity, obviously Davis Monthan has the most to offer. For civil aircraft I believe Roswell, NM, is now leader in terms of numbers stored. You won't get airside but there are good, if distant, views from the perimeter.
For detailed information go to:
cactuswings | Google Groups
You'll find plenty of information on aircraft that can be seen.