How do you get rid of fleas?

we got a kitten about 3/4months ago, about 2months ago we noticed she had fleas, im not sure if shes had them since we got her, or she brought them in. i noticed black "dirt" on her since we had her though, i just thought it was muck. anyway, we used flea powder everywhere, flea tablets, flea spray and flea bombs, they went away for a few days but came back again. we've now put front-line on her but we keep finding fleas on her. 5 saturday, 3sunday and 2monday. we are keeping her in the bathroom at the moment until we have got rid of the fleas, we are giving her water and food and somewhere to sleep. last night we flea powdered the sofa and rug, hoovered them, put flea spray on them as well. we heard vinegar kills them so put a bowl of vinegar on the rug and sofa as well, we caught one in the vinegar. we washed the throw and cushions, and then flea sprayed them. we are going to re-bomb everything on friday. we are hoovering all carpets and wood flooring, spraying them with flea stray, and insect killer, we've put bowls of vinegar through out the house. washing all clothes, using a flea comb on our cat. is there anything else we can do? also can we still use flea powder on the cat if shes got front-line on?