stupid fleas

My pets have fleas. I have tried frontline, vectra(i think thats the name) some kind of pill, hartz, baths in dawn, and so far, it hasn't worked. I need something to get rid of these fleas! HELP! Someone told me something Earth once but I dont remember the full name or have any idea where to get it. My delima: my dog is a Rott, he has very sensitive skin, alot of things(flea shampoo amongst others) make him itch worse then the fleas themselves. the kitties are ok with anything but with grembles thick fur it's hard to keep them off of him. Anyone have any suggestions?