You have to treat the animal, Revolution is one of the best choices out there, you get that from a vet. Flea collars on animals are harmful, as are things like Hartz and other store brands, plus they rarely work. Use only flea preventative from a veterinarian. There are some more natural remedies for treating the house yard instead of bombing, Some work, some don't.. so research around.
Vacuum constantly, and change the bag. Buy a flea collar, cut it up and put it in the vacuum bag. You also have to treat your yard. If you have a shaggy type carpet, put it in the trash. The flea eggs will lie dormant in there and no amount of vaccuuming or bombing/spray will be able to get them. You have to treat in cycles, because fleas live in cycles. You may be killing off all the adult fleas, but then larval and eggs are just fine and dandy.
Also, the pet cannot be in the home when it is being bombed. We went away for a weekend, bombed the house and treated the dog at the same time.