Since Al Gore invented the internet there has been a steady growth in the trend of buying goods online. One of these goods, no matter how much the gun grabber's wish it wasn't so, is firearms.
Where to look
There are two types of websites out there that cater to those looking for guns. National sites and local sites. National sites enable a seller; say in Ohio, to sell guns to a buyer in Texas. Probably the biggest and best-known site for national online gun sales is Gunbroker followed by Gunsamerica , and Gunauction . These are auction type-sites similar to eBay. Ebay itself doesn't permit guns to be sold on their site but does allow parts and magazines.
Regional or local sites are more like online classified ad boards that are restricted to smaller areas. Instead of auction style listings, sellers list an item for a fixed price or trade. Once an agreement is made, transfer is face to face on neutral ground. A good example of this is Armslist , Texas Gun Trader ,and Oregon Guns , etc
Even though it is a violation of their terms and condition to sell firearms on Craigslist, people still list there frequently so it is worth browsing the 'sporting' section ever so often.
How to buy
Once you win an auction (on auction sites) or come to an agreement (on classified sites), now comes the crying. The best way to pay for auction winnings is either by credit card or by postal money order/cashier's check. The card is instant but it's common for sellers to charge an extra 3% or so to cover their fees. On the other hand, a cashier's check or Money order is cheap but you have to mail it, which takes a week or so. Either way, save the cash for face-to-face transactions (bring correct change!).
Please don't fool with PayPal for gun transactions due to their anti-gun polices, and leave your checkbook for paying your mortgage.
Under current legislation, in many states face-to-face transactions between two adult citizens in good standing do not require 'paperwork'. This means that if you work out a local deal through CL, Armslist, etc. and no state law requires a background check, then it is a cash and carry situation. It's always a good idea in these cases to get a bill of sale signed by both parties with an identifying state issued ID number mentioned on the bill as a reference.
If the gun is being shipped to you and its modern (made after 1898) and not blackpowder, you have to get a Federal Firearms License holder involved. For a nominal fee (normally about $30 or up to 10% of the items cost), a local FFL holder will agree to have your auction winning sent to them. They will then take it into their inventory, process the FBI background check on you, keep the required ATF paperwork, and then transfer ownership to you. There are several websites to shop around for FFL holders and usually each auction site also has a listing as well. You can also let your fingers do the walking and call around.
In any situation where you are buying a firearm from someone based on a written description and a few pictures, be careful. Don't take anything for granted and be sure to ask any questions before you bid. If a seller is gruff, or gets defensive, take it as a red flag. Be sure to actually look at the photographs and question anything you see that's funny. If the pictures are very low resolution, dark, or obscured, ask for better ones. By the time you get the gun in your hands after paying for it may be too late.
Now get to clicking!