NOPE
No, you do not need a licence for airsoft guns in the US.
Yes, but you need a licence and this is difficult to obtain. You have to be 18 and you can only get a gun licence for sporting purposes.
You need a licence to purchase one
There is no licencing anywhere for airsoft guns.
Yes, you do- air weapons in the UK require a firearms licence.
Yes
Yes, Black powder guns are extremley dangerous a licence is definitely needed
Yes
Not many at all. VERY very few...only some criminals (as all other countries)
Yes - airsoft toy guns are federally classified as firearms in Australia, so you will need the same license as for a lethal weapon.http://www.airsoftaustralia.com.au/
In order to answer that, we would need to know where you are located, and what you mean by a gun licence. Do you mean a licence to possess (not required here, by the way) a license to carry, a licence to repair, or a licence to sell guns. Please rephrase your question, and give us enough information that we can give you a real answer. Sorry.