Dissasemble the pistol and remove something that will allow it to be reassembled into a functional weapon (although manufacturers and some end-users just take the slide off, wrap it seperately, take out the firing pin and stick it in the mag. well). Package it and seal the box. Don't put anything on the outside that says it's a firearm, and the address can't make it obvious that it is a firearm.
Walk into the Fedex Office. When you get to the service person, say, "I am shipping this package to a Federally Licensed Firearms dealer. The dealer has his license on file with Fedex. The package contains a firearm. The firearm has been disassembled and parts removed so that it will not function." If they are not a newbie, they will tell you no problem, has to go overnight, and do you want to insure it. A pistol will usually cost between $30-40.
IF they're a newbie, they will freak out and summon a manager who looks like Rosie O'Donnell. She will begin interviewing you - even though YOU brought THEM a copy of THEIR rules. Offer to open the package and show them it's been dissasembled - they'll decline! You will then call the gunsmith. The gunsmith will say, loud enough for them to hear it, "If they don't take care of you, just go over to UPS." Then, they will come to their senses and realize they only make money when they ship goods and $30 for two pounds is good work when you can get it.
I've heard that UPS will no longer ship a handgun end-user to FFL - only FFL to FFL but don't know this for a fact. The USPS won't ship handguns, and will only ship rifles between FFL's. The guy from Fedex Ground who delivered 400 rounds of USGI surplus 30.06 ammo told me they don't deliver firearms - or ammunition. Enjoy!