Dino and I buy fish online quite frequently. Most people on sites like
www.aquabid.com will offer a live arrival guarantee if you pay the over night shipping costs.
If you live on a route where the usps (assuming you are in the USA) would normally take two days to deliver, like we do, it is fairly easy to do 2 day shipping (much cheaper).
We live in East Tennessee. Atlanta is our nearest large hub. If we buy fish from the boonies in Maine, they ship to atlanta then to chattanooga then to us. Takes them 2 days normally.
If it were us we would make sure to try to buy from people who do NOT use bag buddies or tranquilizers. We rarely have trouble with buying fish online. We tend to stop buying and we do not ship from october to march normally, just because there are times when the packages are being loaded onto a plane that they may sit outside for an hour or more... that is bad for the fish in cold weather. (We factor in the weather of where we're buying from, the hub it will go through, and the weather here when we purchase fish online.)
I know it sounds complicated, but it is real simple.
Best of luck.