I can't speak from personal experience, but, 300hp+vr6, I believe that many folks choose to buy fish from Aquabid b/c they are "breeder" quality instead of something from a LFS (local fish store). Which if you are interested in breeding, the genetics of the fish, and knowing the genetics of the fish is _very_ important.
If you get a good seller, then _usually_ the fish are okay being shipped. Fish going to petstores are also shipped too (by the local post) and generally speaking, they are in very small bags, etc, I'm not sure if a heat pack or insulation is used, but I'd imagine that the box would have some sort of special label on it making sure that the post office knows it's a living creature.
Most international or non-local breeders will send to what's called a "trans-shipper" so your fish doesn't have as long of a journey all at once. The trans-shipper will feed your fish, change the water, etc etc (at least this is my understanding) and then with in a specified amount of time (usually 2 weeks or so) the fish is express mailed to you.
do you have to collect or can they be delivered??
I'm not sure exactly what you mean by this?
I hope the information above helps to answer your questions......if anyone who has used Aquabid/Ebay/Breeder wants to clarify anything I might have messed up, please feel free to do so
-Ravenwing