Source of ammonia for Nitric Acid

Hi, first post here!

I would like to try to make some nitric acid useing the process in this thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=1851

I could not find mention of where the ammonia came from. Would bubbleing air threw household ammonia (5-10%) or windex work? Since the meth crysis ammonia gas has been strictly regulated and most likely impossible to get. I hope household ammonia can be used without the dry ice technique.