I've found that using the DE on a carpet doesn't work too well. I still had fleas, despite following the container's directions to a tee (I used Flea Away DE powder). Plus, it didn't work too well on Daisy, my cat either. All it did was made her sneeze a lot, even though I didn't use hardly any around her face.
If you are wanting something a little more natural than the OTC products, There is some flea drops called Nature's Guardian that PetSmart sells that are pesticide free (they use special herb oils to kill and repell fleas).
Since my cat get's reactions to most OTC flea drops (even Frontline and Advantage), I use a oral flea medicine called Program that you put in a cat's food once a month. It makes it to where the flea eggs can't develop (sorta like birth control for fleas). Capstar is another pesticide-free oral flea medicine, that you can give a cat or dog as often as once a day or as infrequent as once a week. It only kills adult fleas. www.jeffers.com
both sell these 2 flea items.
(single mommy to Emma, 3 years and Angela, 2 years)