Radioshack in the mall on D ring has these items, never tried them personally however as long as the connecting cables are of decent quality then interference from outside sources should not be an issue.
Motion sensors etc with timers (for night time or whilst out of the house) could also be integrated for 100% piece of mind.
As long as you dont have them pointed at neighbours bedroom windows then no privacy law should be broken either.

We came we saw we were Qatarized