I have used flea spray from the pet shop in the past on a 2 peice suite that was ridden in fleas a year a go. worked a treat!
the only problem is that they are sold in small bottles so might be hard/costly to do a whole carpet never mind the whole house!
There is great product that is sold in a sachet that works real good. cant think of the name tho
i'll double check my bookmarks
tony