A property owner can give you an easement for the air rights of their property, which can allow you to put your own structure over their property or prevent them from putting a structure over their property (depending on the terms of the easement). For instance, a railroad might sell the air rights to an urban rail yard to a private developer so that the developer can put buildings over top of the yard. A high-rise owner might buy an easement for a neighboring property that bans them from building above a certain height in order to keep the views from the high-rise unblocked.
However, a property owner can't sell you rights that they themselves don't have. The US government has exclusive sovereignty over US airspace, and there's a public right of transit through navigable airspace (defined as airspace above minimum safe flight altitudes). While the traditional rule was that a property owner owned their land up to infinity, with the development of airplanes this rule has been changed to significantly limit the rights of property owners. The FAA doesn't limit how tall a property owner can build (although too-tall structures can be declared hazards to navigation, which can cause issues with planning boards or insurance companies). However, if there are no obstructions, the airspace above 500 feet in rural areas (in built-up areas it depends on local obstructions) is open for pilots to fly through.
The only way to get obstruction-free airspace restricted is to try to get the FAA to issue a flight restriction. If you're trying to get large swaths of airspace restricted, this is extremely unlikely to happen.