We bought a spray from our local pet shop, think it was about �9, can't remember the name sorry but apparantly it is the only one that really works and all pet shops should sell it.
Make sure you cover up fishtanks and move any other animals out of the house. Spray the carpet in each room and leave for 30 mins I think it was. Worked a treat!!
We used one of those Bob Martin Flea Foggers. You set them off in a room, close the door and leave it for a period of time, then hoover. The effect lasted for ages, it doesn't only kill off fleas and their attendant eggs, but anything insecty that comes into the room for months afterwards - quite disturbing to see a fly buzz in weeks later, land on the floor, and then do one of those wierd fly-ish death dances before croaking in a matter of minutes.