welcome kdzine...

i suspect several people have at least some experience with moss and or bonsai..
the main topic Board to ask in would be 'other plants', if the question is bonsai, then under 'bonsai'. Though you could also search 'garden bonsai'.
for moss, one of the last topics was moss wall substrates.
as you ask about how to order 'real moss',

are you saying that real moss does not grow in Philly?
I would think that moss is easy to find on the north side of most places in Philly...
welcome to the forum.. edzard