If they are a quality LFS, they will pack the fish with oxygen...so you do not need an airstone. This is preferable. Give them a call and see.
Tell them you have a decent trip. They should put it in a larger bag with oxygen and this will be sufficient for many many many many hours.
Then get a cooler to keep the temperature constant, and also keep the bag dark. Again, a good store probably has a styro shipping box to give you.
2 hours is really not much, and IMO does not require particularly intensive preparation.