You can find alot of sites that have book value, but I always use Gunbroker.com. It is an online gun auction site like Ebay. It lets you find out what gun is worth nationally.
The value of a 410 shotgun depends on the make and model of the gun. If it is a single shot and made by Stevens the value would be approximately $70.00; however if it is a side by side the value is more. There has been some of these guns on the Internet for $55,000.00.
You only get an "appraised" value if you pay an appraiser to examine the firearm. You could get an "estimated" value on the internet if you would tell us the model and condition. Or you can look on internet auction sites (gunsamerica.com, etc) and find out similar guns are selling for.
Assuming a used gun, most likely between $500 to $1000 dollars, although higher grade guns could be worth more. This is dependent on conditon and model. Benelli makes very fine guns. If you get the exact model of the gun you can do some research on the internet and get an idea of value.
The Library
The internet. There are many online Airsoft stores that sell Tokyo Marui guns.
You can buy guns by getting on the internet open your pda and their is a place called liberty city gun shop you can buy guns their
depends on the type of rifle / pistol
most toy stores and the internet
About $75, depending on condition. These have always been low value guns.
There is no one place that has what you want.
Guns and booze.
Contact the maker, buy a book, post on the internet.