Usually near the outdoor/hunting section which is usually adjacent to the fishing section. If you're asking about a whole airsoft-dedicated store, you're best chances are looking online for things, because there are very few whole airsoft stores. Most of what you'll find in your sporting goods store isn't all that great of stuff anyways.
Yes
Most large sporting goods stores carry air soft guns, or on the web. Check Amazon.com
Sporting good stores like Cabelas, Basspro, Dicks or Wallmart, airsoft stores and fields, or online.
Air soft is the common term, soft air is the correct name.
Anything is possible but not likely with air soft. But they do hurt when they hit you. Simply don't shoot anyone with an air soft gun. Treat it like a real gun.
For an air soft gun it's average. Air soft guns can reach 400 FPS.
An air soft gun can possibly kill a rattle snake but it depends on the gun and where you hit it
If you are asking about the Air Soft gun, it can be as little as $10, to well over $300. Good inexpensive ones can be found for around $20 at sporting goods stores like Big 5.
you can't!
No because in Philadelphia it illegal to have type of air soft for example pellet paintball and bb
It depends on what you mean. You can buy Air-Soft guns at some sporting goods stores. An Air-Soft gun looks like a real gun, but fires plastic pellets. They are available in several different models and are made to the same specifications as the real gun they are a copy of, so they will fit into a gun case or holster designed for that same gun. You can also buy training guns at some gun stores, or through companies like Blackhawk.
A BB gun has a very hard projectile and will cause more damage to a person than an air soft pellet.