> Most networks like Flight Aware allow owners to blacklist aircraft such that their tracks do not appear on the site.

Do you know more about how this is done? Is there a fixed price list for this service? Can one "buy" it online? Is there some sort of registry that is shared between networks?

> Additionally military aircraft are typically not reported.

While I'm sure the military can turn off transponders at will, I presume (?) they often fly with them on. Can these signals be tracked with "standard" gear when they are on?