I agree, there is no simple fix, so you must prepare yourself for a battle.
Two things I would immediately recommend (as I have been through the scenario you describe), is this:
1.) You
must do a whole-yard treatment for fleas - I was lucky to find a local pesticide dealer in my area, a small privately owned shop that sells industrial and commercial grade pesticide products. The fellow in there was extremely helpful and suggested a product called Talstar, which came in granular form and is easily dispensed in the yard with an ordinary handheld seeding dispenser.
2.) At the same time, you must bath each of your pets with a good flea/tick shampoo to kill the living fleas on their bodies. Following this, I use Advantix (available through local vet offices) - it's like Frontline, where you squeeze the liquid from a tube onto their shoulder area, but this stuff actually works. It's a monthly dose, and they're about $20/dose at my vet. I've used all the other brands before, and I swear by this stuff - it actually does work.
3.) The third aspect of this battle is to rid your carpet and upholstery from the fleas and eggs that have been deposited there. This is the trickiest part - b/c you may not get all of the eggs, so two weeks later, voila - you're going to have some fleas appear again. The trick here is to utilize a good flea spray that they make for carpet and fabrics, and vacuum the HELL out of your home, I mean literally multiple times in a row.
This is the three pronged attack that I ended up having to do, and we've been flea-free ever since. The key is to do all of these simultaneously, so you're not undermining one of the three by not doing the other.
Hope that helps - good luck!