Sounds like you are doing some great research before you get the puppy, good job
Here is a site that specialises in natural flea treatments.
I would avoid using any chemical based products until the pup is a little older.
There are some flea preventions available for puppies but I think these would be better on a little one...
There are yard sprays as well as dog shampoos on this site.
Another natural alternative is to feed your dog a little garlic in with his food or buy a dog shampoo with lavendar... fleas hate it.
Apparently apple cider vinegar works as a flea prevention too, you just bathe your dog in it (I have not tried this only read about it)
Flea Free: Garlic Flea Prevention